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1
Alper, Mark. "Biology and Materials? Part I." MRS Bulletin 17, no. 10 (1992): 24–26. http://dx.doi.org/10.1557/s0883769400046431.
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Poets and philosophers have, through the ages, viewed organisms as the embodiment of the mysterious “Vital Force,” a unique non-earthly element required for the functioning of life processes.Biologists have seen, in living organisms, an adaptive, self-reproducing, evolving collection of molecules acting solely according to the laws of chemistry and physics.Historians speak of the iron or bronze ages and, more recently of the plastics (polymers) and the silicon ages. Materials science departments speak of metals, alloys, ceramics, and perhaps polymers—but not of genes.The “common man” has, it must be admitted, seen living organisms as a source of useful and important materials—wood for building; cotton, silk, and other fibers for textiles; horn, shell, and bone for tools and weapons; fats for lubricants; fur for clothingBut, in fact, few of us now think of materials when we think of living things. Neither do we think of DNA, protein, and carbohydrates when we think of materials.No, biologists have not been blackballed by materials scientists, chemists, and physicists. Until recently, they neither understood the processes by which life produces its materials nor even conceived of manipulating those processes to tailor the properties of the materials to our needs. Only within the past few years has the “biological revolution” expanded our understanding of the molecular basis for biological phenomena and our ability to control them. It is only now, for the first time, that one can point to a legitimate field of science based on mimicking, adapting, and controlling biological systems with the goal of producing novel materials with important, unique, and useful properties.
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Whitesides, George M. "Organic Materials Science." MRS Bulletin 27, no. 1 (2002): 56–65. http://dx.doi.org/10.1557/mrs2002.22.
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AbstractThe following article is based on the presentation given by George M. Whitesides, recipient of the 2000 MRS Von Hippel Award, the Materials Research Society's highest honor, at the 2000 MRS Fall Meeting in Boston on November 29, 2000. Whitesides was cited for “bringing fundamental concepts of organic chemistry and biology into materials science and engineering, through his pioneering research on surface modification, self-assembly, and soft lithography.” The article focuses on the growing role of organic chemistry in materials science. Historically, that role has been to provide organic polymers for use in structures, films, fibers, coatings, and so on. Organic chemistry is now emerging as a crucial part of three new areas in materials science. First, it provides materials with complex functionality. Second, it is the bridge between materials science and biology/medicine. Building an interface between biological systems and electronic or optical systems requires close attention to the molecular level of that interface. Third, organic chemistry provides a sophisticated synthetic entry into nanomaterials. Organic molecules are, in fact, exquisitely fabricated nanostructures, assembled with precision on the level of individual atoms. Colloids are a related set of nanostructures, and organic chemistry contributes importantly to their preparation as well.
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Refaat, Doaa, Mohamed G. Aggour, Ahmed A. Farghali, et al. "Strategies for Molecular Imprinting and the Evolution of MIP Nanoparticles as Plastic Antibodies—Synthesis and Applications." International Journal of Molecular Sciences 20, no. 24 (2019): 6304. http://dx.doi.org/10.3390/ijms20246304.
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Materials that can mimic the molecular recognition-based functions found in biology are a significant goal for science and technology. Molecular imprinting is a technology that addresses this challenge by providing polymeric materials with antibody-like recognition characteristics. Recently, significant progress has been achieved in solving many of the practical problems traditionally associated with molecularly imprinted polymers (MIPs), such as difficulties with imprinting of proteins, poor compatibility with aqueous environments, template leakage, and the presence of heterogeneous populations of binding sites in the polymers that contribute to high levels of non-specific binding. This success is closely related to the technology-driven shift in MIP research from traditional bulk polymer formats into the nanomaterial domain. The aim of this article is to throw light on recent developments in this field and to present a critical discussion of the current state of molecular imprinting and its potential in real world applications.
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Valluzzi, R., S. Winkler, D. Wilson, and D. L. Kaplan. "Silk: molecular organization and control of assembly." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 357, no. 1418 (2002): 165–67. http://dx.doi.org/10.1098/rstb.2001.1032.
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The interface between the science and engineering of biology and materials is an area of growing interest. One of the goals of this field is to utilize biological synthesis and processing of polymers as a route to gain insight into topics such as molecular recognition, self–assembly and the formation of materials with well–defined architectures. The biological processes involved in polymer synthesis and assembly can offer important information on fundamental interactions involved in the formation of complex material architectures, as well as practical knowledge into new and important materials related to biomaterial uses and tissue engineering needs. Classic approaches in biology, including genetic engineering, controlled microbial physiology and enzymatic synthesis, are prototypical methods used to control polymer structure and chemistry, including stereoselectivity and regioselectivity, to degrees unattainable using traditional synthetic chemistry. This type of control can lead to detailed and systematic studies of the formation of the structural hierarchy in materials and the subsequent biological responses to these materials.
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Huang, Zhen, and Roman Boulatov. "Chemomechanics with molecular force probes." Pure and Applied Chemistry 82, no. 4 (2010): 931–51. http://dx.doi.org/10.1351/pac-con-09-11-36.
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Chemomechanics is an emerging area at the interface of chemistry, materials science, physics, and biology that aims at quantitative understanding of reaction dynamics in multiscale phenomena. These are characterized by correlated directional motion at multiple length scales—from molecular to macroscopic. Examples include reactions in stressed materials, in shear flows, and at propagating interfaces, the operation of motor proteins, ion pumps, and actuating polymers, and mechanosensing. To explain the up to 1015-fold variations in reaction rates in multiscale phenomena—which are incompatible within the standard models of chemical kinetics—chemomechanics relies on the concept of molecular restoring force. Molecular force probes are inert molecules that allow incremental variations in restoring forces of diverse reactive moieties over hundreds of piconewtons (pN). Extending beyond the classical studies of reactions of strained molecules, molecular force probes enable experimental explorations of how reaction rates and restoring forces are related. In this review, we will describe the utility of one such probe—stiff stilbene. Various reactive moieties were incorporated in inert linkers that constrained stiff stilbene to highly strained macrocycles. Such series provided the first direct experimental validation of the most popular chemomechanical model, demonstrated its predictive capabilities, and illustrated the diversity of relationships between reaction rates and forces.
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Kamarudin, Muhammad Akmal, Shahrir Razey Sahamir, Robi Shankar Datta, Bui Duc Long, Mohd Faizul Mohd Sabri, and Suhana Mohd Said. "A Review on the Fabrication of Polymer-Based Thermoelectric Materials and Fabrication Methods." Scientific World Journal 2013 (2013): 1–17. http://dx.doi.org/10.1155/2013/713640.
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Thermoelectricity, by converting heat energy directly into useable electricity, offers a promising technology to convert heat from solar energy and to recover waste heat from industrial sectors and automobile exhausts. In recent years, most of the efforts have been done on improving the thermoelectric efficiency using different approaches, that is, nanostructuring, doping, molecular rattling, and nanocomposite formation. The applications of thermoelectric polymers at low temperatures, especially conducting polymers, have shown various advantages such as easy and low cost of fabrication, light weight, and flexibility. In this review, we will focus on exploring new types of polymers and the effects of different structures, concentrations, and molecular weight on thermoelectric properties. Various strategies to improve the performance of thermoelectric materials will be discussed. In addition, a discussion on the fabrication of thermoelectric devices, especially suited to polymers, will also be given. Finally, we provide the challenge and the future of thermoelectric polymers, especially thermoelectric hybrid model.
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Badami, Vijetha, and Bharat Ahuja. "Biosmart Materials: Breaking New Ground in Dentistry." Scientific World Journal 2014 (February 2, 2014): 1–7. http://dx.doi.org/10.1155/2014/986912.
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By definition and general agreement, smart materials are materials that have properties which may be altered in a controlled fashion by stimuli, such as stress, temperature, moisture, pH, and electric or magnetic fields. There are numerous types of smart materials, some of which are already common. Examples include piezoelectric materials, which produce a voltage when stress is applied or vice versa, shape memory alloys or shape memory polymers which are thermoresponsive, and pH sensitive polymers which swell or shrink as a response to change in pH. Thus, smart materials respond to stimuli by altering one or more of their properties. Smart behaviour occurs when a material can sense some stimulus from its environment and react to it in a useful, reliable, reproducible, and usually reversible manner. These properties have a beneficial application in various fields including dentistry. Shape memory alloys, zirconia, and smartseal are examples of materials exhibiting a smart behavior in dentistry. There is a strong trend in material science to develop and apply these intelligent materials. These materials would potentially allow new and groundbreaking dental therapies with a significantly enhanced clinical outcome of treatments.
8
Saylan, Yeşeren, Özgecan Erdem, Fatih Inci, and Adil Denizli. "Advances in Biomimetic Systems for Molecular Recognition and Biosensing." Biomimetics 5, no. 2 (2020): 20. http://dx.doi.org/10.3390/biomimetics5020020.
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Understanding the fundamentals of natural design, structure, and function has pushed the limits of current knowledge and has enabled us to transfer knowledge from the bench to the market as a product. In particular, biomimicry―one of the crucial strategies in this respect―has allowed researchers to tackle major challenges in the disciplines of engineering, biology, physics, materials science, and medicine. It has an enormous impact on these fields with pivotal applications, which are not limited to the applications of biocompatible tooth implants, programmable drug delivery systems, biocompatible tissue scaffolds, organ-on-a-chip systems, wearable platforms, molecularly imprinted polymers (MIPs), and smart biosensors. Among them, MIPs provide a versatile strategy to imitate the procedure of molecular recognition precisely, creating structural fingerprint replicas of molecules for biorecognition studies. Owing to their affordability, easy-to-fabricate/use features, stability, specificity, and multiplexing capabilities, host-guest recognition systems have largely benefitted from the MIP strategy. This review article is structured with four major points: (i) determining the requirement of biomimetic systems and denoting multiple examples in this manner; (ii) introducing the molecular imprinting method and reviewing recent literature to elaborate the power and impact of MIPs on a variety of scientific and industrial fields; (iii) exemplifying the MIP-integrated systems, i.e., chromatographic systems, lab-on-a-chip systems, and sensor systems; and (iv) closing remarks.
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Hu, Xiao, Samuel Ricci, Sebastian Naranjo, Zachary Hill, and Peter Gawason. "Protein and Polysaccharide-Based Electroactive and Conductive Materials for Biomedical Applications." Molecules 26, no. 15 (2021): 4499. http://dx.doi.org/10.3390/molecules26154499.
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Electrically responsive biomaterials are an important and emerging technology in the fields of biomedical and material sciences. A great deal of research explores the integral role of electrical conduction in normal and diseased cell biology, and material scientists are focusing an even greater amount of attention on natural and hybrid materials as sources of biomaterials which can mimic the properties of cells. This review establishes a summary of those efforts for the latter group, detailing the current materials, theories, methods, and applications of electrically conductive biomaterials fabricated from protein polymers and polysaccharides. These materials can be used to improve human life through novel drug delivery, tissue regeneration, and biosensing technologies. The immediate goal of this review is to establish fabrication methods for protein and polysaccharide-based materials that are biocompatible and feature modular electrical properties. Ideally, these materials will be inexpensive to make with salable production strategies, in addition to being both renewable and biocompatible.
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Glosz, Karolina, Agnieszka Stolarczyk, and Tomasz Jarosz. "Siloxanes—Versatile Materials for Surface Functionalisation and Graft Copolymers." International Journal of Molecular Sciences 21, no. 17 (2020): 6387. http://dx.doi.org/10.3390/ijms21176387.
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Siloxanes are adaptable species that have found extensive applications as versatile materials for functionalising various surfaces and as building blocks for polymers and hybrid organic-inorganic systems. The primary goal of this review is to report on and briefly explain the most relevant recent developments related to siloxanes and their applications, particularly regarding surface modification and the synthesis of graft copolymers bearing siloxane or polysiloxane segments. The key strategies for both functionalisation and synthesis of siloxane-bearing polymers are highlighted, and the various trends in the development of siloxane-based materials and the intended directions of their applications are explored.
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Rydz, Joanna, Wanda Sikorska, Mariya Kyulavska, and Darinka Christova. "Polyester-Based (Bio)degradable Polymers as Environmentally Friendly Materials for Sustainable Development." International Journal of Molecular Sciences 16, no. 1 (2014): 564–96. http://dx.doi.org/10.3390/ijms16010564.
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González-Henríquez, Carmen, Mauricio Sarabia-Vallejos, and Juan Rodríguez Hernandez. "Antimicrobial Polymers for Additive Manufacturing." International Journal of Molecular Sciences 20, no. 5 (2019): 1210. http://dx.doi.org/10.3390/ijms20051210.
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Three-dimensional (3D) printing technologies can be widely used for producing detailed geometries based on individual and particular demands. Some applications are related to the production of personalized devices, implants (orthopedic and dental), drug dosage forms (antibacterial, immunosuppressive, anti-inflammatory, etc.), or 3D implants that contain active pharmaceutical treatments, which favor cellular proliferation and tissue regeneration. This review is focused on the generation of 3D printed polymer-based objects that present antibacterial properties. Two main different alternatives of obtaining these 3D printed objects are fully described, which employ different polymer sources. The first one uses natural polymers that, in some cases, already exhibit intrinsic antibacterial capacities. The second alternative involves the use of synthetic polymers, and thus takes advantage of polymers with antimicrobial functional groups, as well as alternative strategies based on the modification of the surface of polymers or the elaboration of composite materials through adding certain antibacterial agents or incorporating different drugs into the polymeric matrix.
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Othman, Siti Amira, and Shahidan Radiman. "Role of Horseradish Peroxidase in Polypyrrole Conductivity." Solid State Phenomena 268 (October 2017): 370–73. http://dx.doi.org/10.4028/www.scientific.net/ssp.268.370.
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Immobilise enzymes can offer many advantages over their soluble forms making this is a topic of active research in enzyme technology for industrial applications. There are various methods for enzyme immobilization as well as support materials. The methods and supports used for immobilisation of certain enzyme are chosen to ensure the highest retention of activity and its stability. Enzyme Horseradish peroxidise (HRP) was used extensively in molecular biology applications primarily for its ability to amplify a weak signal and increase the detectability of a target molecules. Recently class of conducting polymers are used as a polymeric support. Among the family a conducting polymer, polypyrrole (PPY) has intensively been used for various reason because of its unique properties such as ease of synthesis by chemical or electrochemical oxidative polymerization of the monomers, role as a polymeric support and also have potential in various field . It has alternating single and double carbon-carbon bonds along the polymeric chains. The highly conjugated polymer chain can be assigned reversible chemical, electrochemical and physical properties controlled by a doping/ de-doping process, which makes this polymers very attractive as transducer materials in various sensing devices. This paper reports the process of immobilised enzymes on polymeric substrate and the role of enzymes in PPY conductivity. The characterization was done using UV-Visible, FTIR and four point probe.
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Paradowska-Stolarz, Anna, Mieszko Wieckiewicz, Artur Owczarek, and Joanna Wezgowiec. "Natural Polymers for the Maintenance of Oral Health: Review of Recent Advances and Perspectives." International Journal of Molecular Sciences 22, no. 19 (2021): 10337. http://dx.doi.org/10.3390/ijms221910337.
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The success of modern dental treatment is strongly dependent on the materials used both temporarily and permanently. Among all dental materials, polymers are a very important class with a wide spectrum of applications. This review aims to provide a state-of-the-art overview of the recent advances in the field of natural polymers used to maintain or restore oral health. It focuses on the properties of the most common proteins and polysaccharides of natural origin in terms of meeting the specific biological requirements in the increasingly demanding field of modern dentistry. The use of naturally derived polymers in different dental specialties for preventive and therapeutic purposes has been discussed. The major fields of application cover caries and the management of periodontal diseases, the fabrication of membranes and scaffolds for the regeneration of dental structures, the manufacturing of oral appliances and dentures as well as providing systems for oral drug delivery. This paper also includes a comparative characteristic of natural and synthetic dental polymers. Finally, the current review highlights new perspectives, possible future advancements, as well as challenges that may be encountered by researchers in the field of dental applications of polymers of natural origin.
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Kwon, Jae-Sung, Ji-Yeong Kim, Utkarsh Mangal, et al. "Durable Oral Biofilm Resistance of 3D-Printed Dental Base Polymers Containing Zwitterionic Materials." International Journal of Molecular Sciences 22, no. 1 (2021): 417. http://dx.doi.org/10.3390/ijms22010417.
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Poly(methyl methacralyate) (PMMA) has long been used in dentistry as a base polymer for dentures, and it is recently being used for the 3D printing of dental materials. Despite its many advantages, its susceptibility to microbial colonization remains to be overcome. In this study, the interface between 3D-printed PMMA specimens and oral salivary biofilm was studied following the addition of zwitterionic materials, 2-methacryloyloxyethyl phosphorylcholine (MPC) or sulfobetaine methacrylate (SB). A significant reduction in bacterial and biofilm adhesions was observed following the addition of MPC or SB, owing to their protein-repellent properties, and there were no significant differences between the two test materials. Although the mechanical properties of the tested materials were degraded, the statistical value of the reduction was minimal and all the properties fulfilled the requirements set by the International Standard, ISO 20795-2. Additionally, both the test materials maintained their resistance to biofilm when subjected to hydrothermal fatigue, with no further deterioration of the mechanical properties. Thus, novel 3D-printable PMMA incorporated with MPC or SB shows durable oral salivary biofilm resistance with maintenance of the physical and mechanical properties.
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Armentano, Ilaria, Carla Renata Arciola, Elena Fortunati, et al. "The Interaction of Bacteria with Engineered Nanostructured Polymeric Materials: A Review." Scientific World Journal 2014 (2014): 1–18. http://dx.doi.org/10.1155/2014/410423.
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Bacterial infections are a leading cause of morbidity and mortality worldwide. In spite of great advances in biomaterials research and development, a significant proportion of medical devices undergo bacterial colonization and become the target of an implant-related infection. We present a review of the two major classes of antibacterial nanostructured materials: polymeric nanocomposites and surface-engineered materials. The paper describes antibacterial effects due to the induced material properties, along with the principles of bacterial adhesion and the biofilm formation process. Methods for antimicrobial modifications of polymers using a nanocomposite approach as well as surface modification procedures are surveyed and discussed, followed by a concise examination of techniques used in estimating bacteria/material interactions. Finally, we present an outline of future sceneries and perspectives on antibacterial applications of nanostructured materials to resist or counteract implant infections.
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Lech, Adam, Beata A. Butruk-Raszeja, Tomasz Ciach, et al. "Surface Modification of PLLA, PTFE and PVDF with Extreme Ultraviolet (EUV) to Enhance Cell Adhesion." International Journal of Molecular Sciences 21, no. 24 (2020): 9679. http://dx.doi.org/10.3390/ijms21249679.
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Recently, extreme ultraviolet (EUV) radiation has been increasingly used to modify polymers. Properties such as the extremely short absorption lengths in polymers and the very strong interaction of EUV photons with materials may play a key role in achieving new biomaterials. The purpose of the study was to examine the impact of EUV radiation on cell adhesion to the surface of modified polymers that are widely used in medicine: poly(tetrafluoroethylene) (PTFE), poly (vinylidene fluoride) (PVDF), and poly-L-(lactic acid) (PLLA). After EUV surface modification, which has been performed using a home-made laboratory system, changes in surface wettability, morphology, chemical composition and cell adhesion polymers were analyzed. For each of the three polymers, the EUV radiation differently effects the process of endothelial cell adhesion, dependent of the parameters applied in the modification process. In the case of PVDF and PTFE, higher cell number and cellular coverage were obtained after EUV radiation with oxygen. In the case of PLLA, better results were obtained for EUV modification with nitrogen. For all three polymers tested, significant improvements in endothelial cell adhesion after EUV modification have been demonstrated.
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Plota, Angelika, and Anna Masek. "Plant-Origin Stabilizer as an Alternative of Natural Additive to Polymers Used in Packaging Materials." International Journal of Molecular Sciences 22, no. 8 (2021): 4012. http://dx.doi.org/10.3390/ijms22084012.
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Over the past 25 years, cannabis plants have gained major popularity in the research community. This study aimed to evaluate the antioxidant capacity and stabilization efficiency of cannabidiol (CBD) extract in two different polymers: polylactide (PLA) and ethylene–norbornene copolymer (Topas) that are used in packaging materials more often. The research technology included weathering in a special chamber, surface free energy and color change measurements, surface morphology and Fourier-transform infrared spectroscopy (FTIR) analysis, thermogravimetry, and determination of the oxidation induction time or temperature (OIT) values, based on which the effectiveness of the cannabidiol extract could be estimated. Obtained results showed that the addition of CBD to polymer mixtures significantly increased their resistance to oxidation, and it can be used as a natural stabilizer for polymeric products. Moreover, samples with cannabidiol changed their coloration as a result of weathering. Therefore, this natural additive can also be considered as a colorimetric indicator of aging that informs about the changes in polymeric materials during their lifetime. On the other hand, surface properties of samples with cannabidiol content did not alter much compared to pure Topas and PLA.
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Municoy, Sofia, María I. Álvarez Echazú, Pablo E. Antezana, et al. "Stimuli-Responsive Materials for Tissue Engineering and Drug Delivery." International Journal of Molecular Sciences 21, no. 13 (2020): 4724. http://dx.doi.org/10.3390/ijms21134724.
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Smart or stimuli-responsive materials are an emerging class of materials used for tissue engineering and drug delivery. A variety of stimuli (including temperature, pH, redox-state, light, and magnet fields) are being investigated for their potential to change a material’s properties, interactions, structure, and/or dimensions. The specificity of stimuli response, and ability to respond to endogenous cues inherently present in living systems provide possibilities to develop novel tissue engineering and drug delivery strategies (for example materials composed of stimuli responsive polymers that self-assemble or undergo phase transitions or morphology transformations). Herein, smart materials as controlled drug release vehicles for tissue engineering are described, highlighting their potential for the delivery of precise quantities of drugs at specific locations and times promoting the controlled repair or remodeling of tissues.
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Chomicki, Dariusz, Oksana Kharchenko, Lukasz Skowronski, et al. "Physico-Chemical and Light-Induced Properties of Quinoline Azo-dyes Polymers." International Journal of Molecular Sciences 21, no. 16 (2020): 5755. http://dx.doi.org/10.3390/ijms21165755.
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We present investigation of optical and photochromic properties as well as of surface quality of thin films of novel methacrylic polymers with 8-hydroxyquinoline azo-dyes in side-chain. Additionally, thermal stability of polymer powders was examined and their glass transition temperature was determined. Optical properties (extinction coefficient and refractive index) were determined by spectroscopic ellipsometry (SE) combined with absorbance measurements. Photoresponsive behavior was investigated by determination of photoisomerization rates under irradiation with unpolarized 365 nm light, as well as by conduction of holographic grating inscription experiment. Thin film quality was determined by atomic force microscopy (AFM) measurements. Thermal analysis was performed by thermogravimetric (TG), derivative thermogravimetric (DTG) and differential scanning calorimetry (DSC) measurements. We found that optical properties as well as photoisomerization rates of investigated polymers are dependent on the substituent in the para position of the phenyl ring. Surface relief grating inscription was successfully generated only for materials with chromophores containing dimethylamino (N(CH3)2) and methyl (CH3) substituents, but all materials exhibited birefringence grating in the bulk. Surface of most thin films was very smooth, but its quality was impaired by neutral (H) as well as carboxyl (COOH) substituent. Thermal stability of copolymers with side-chain chromophores was improved compared to pure poly(methyl methacrylate) (PMMA).
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Latos-Brozio, Malgorzata, and Anna Masek. "The Application of (+)-Catechin and Polydatin as Functional Additives for Biodegradable Polyesters." International Journal of Molecular Sciences 21, no. 2 (2020): 414. http://dx.doi.org/10.3390/ijms21020414.
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Plant polyphenols are a huge group of compounds with a wide spectrum of applications. Substances from this group have been used in polymer materials such as stabilizers, dyes, indicators, fungicides, and bactericides, especially in new generation packaging materials. The aim of this study is to obtain environmentally friendly materials based on the biodegradable aliphatic polyesters, polylactide (PLA) and polyhydroxyalkanoate (PHA), with plant functional additives, (+)-catechin and polydatin. These natural polyphenols (polydatin and (+)-catechin) have not been used so far in polymer materials (especially in biodegradable polyesters) as stabilizers, dyes, and indicators of aging. The application of polydatin and (+)-catechin as multifunctional additives for biodegradable polymers is a scientific novelty. This paper presents the following analyses of polyester materials: SEM microscopy, wide angle x-ray diffraction, mechanical properties, thermal analysis, surface free energy analysis, and determination of change of color after controlled UV exposure, thermal oxidation and weathering. Both PLA and PHA polyesters were characterized by higher resistance to oxidation and greater resistance to degradation under the influence of UV radiation. In addition, (+)-catechin was used simultaneously as a dye and an indicator of the aging time of polymeric materials. In contrast, polydatin did not dye polymers, but was a very good indicator of their lifetime, changing color under the influence of various external factors. Both polyphenols can be successfully used as natural additives for pro-ecological polyesters.
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Cheng, Xiaoxiao, Tengfei Miao, Yilin Qian, Zhengbiao Zhang, Wei Zhang, and Xiulin Zhu. "Supramolecular Chirality in Azobenzene-Containing Polymer System: Traditional Postpolymerization Self-Assembly Versus In Situ Supramolecular Self-Assembly Strategy." International Journal of Molecular Sciences 21, no. 17 (2020): 6186. http://dx.doi.org/10.3390/ijms21176186.
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Recently, the design of novel supramolecular chiral materials has received a great deal of attention due to rapid developments in the fields of supramolecular chemistry and molecular self-assembly. Supramolecular chirality has been widely introduced to polymers containing photoresponsive azobenzene groups. On the one hand, supramolecular chiral structures of azobenzene-containing polymers (Azo-polymers) can be produced by nonsymmetric arrangement of Azo units through noncovalent interactions. On the other hand, the reversibility of the photoisomerization also allows for the control of the supramolecular organization of the Azo moieties within polymer structures. The construction of supramolecular chirality in Azo-polymeric self-assembled system is highly important for further developments in this field from both academic and practical points of view. The postpolymerization self-assembly strategy is one of the traditional strategies for mainly constructing supramolecular chirality in Azo-polymers. The in situ supramolecular self-assembly mediated by polymerization-induced self-assembly (PISA) is a facile one-pot approach for the construction of well-defined supramolecular chirality during polymerization process. In this review, we focus on a discussion of supramolecular chirality of Azo-polymer systems constructed by traditional postpolymerization self-assembly and PISA-mediated in situ supramolecular self-assembly. Furthermore, we will also summarize the basic concepts, seminal studies, recent trends, and perspectives in the constructions and applications of supramolecular chirality based on Azo-polymers with the hope to advance the development of supramolecular chirality in chemistry.
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Kraśniewska, Karolina, Sabina Galus, and Małgorzata Gniewosz. "Biopolymers-Based Materials Containing Silver Nanoparticles as Active Packaging for Food Applications–A Review." International Journal of Molecular Sciences 21, no. 3 (2020): 698. http://dx.doi.org/10.3390/ijms21030698.
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Packaging is an integral part of food products, allowing the preservation of their quality. It plays an important role, protecting the packed product from external conditions, maintaining food quality, and improving properties of the packaged food during storage. Nevertheless, commonly used packaging based on synthetic non-biodegradable polymers causes serious environmental pollution. Consequently, numerous recent studies have focused on the development of biodegradable packaging materials based on biopolymers. In addition, biopolymers may be classified as active packaging materials, since they have the ability to carry different active substances. This review presents the latest updates on the use of silver nanoparticles in packaging materials based on biopolymers. Silver nanoparticles have become an interesting component of biodegradable biopolymers, mainly due to their antimicrobial properties that allow the development of active food packaging materials to prolong the shelf life of food products. Furthermore, incorporation of silver nanoparticles into biopolymers may lead to the development of materials with improved physical-mechanical properties.
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Campuzano, Susana, María Pedrero, Paloma Yáñez-Sedeño, and José Pingarrón. "Antifouling (Bio)materials for Electrochemical (Bio)sensing." International Journal of Molecular Sciences 20, no. 2 (2019): 423. http://dx.doi.org/10.3390/ijms20020423.
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(Bio)fouling processes arising from nonspecific adsorption of biological materials (mainly proteins but also cells and oligonucleotides), reaction products of neurotransmitters oxidation, and precipitation/polymerization of phenolic compounds, have detrimental effects on reliable electrochemical (bio)sensing of relevant analytes and markers either directly or after prolonged incubation in rich-proteins samples or at extreme pH values. Therefore, the design of antifouling (bio)sensing interfaces capable to minimize these undesired processes is a substantial outstanding challenge in electrochemical biosensing. For this purpose, efficient antifouling strategies involving the use of carbon materials, metallic nanoparticles, catalytic redox couples, nanoporous electrodes, electrochemical activation, and (bio)materials have been proposed so far. In this article, biomaterial-based strategies involving polymers, hydrogels, peptides, and thiolated self-assembled monolayers are reviewed and critically discussed. The reported strategies have been shown to be successful to overcome (bio)fouling in a diverse range of relevant practical applications. We highlight recent examples for the reliable sensing of particularly fouling analytes and direct/continuous operation in complex biofluids or harsh environments. Opportunities, unmet challenges, and future prospects in this field are also pointed out.
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Abbas, Tariq O., Huseyin C. Yalcin, and Cristian P. Pennisi. "From Acellular Matrices to Smart Polymers: Degradable Scaffolds that are Transforming the Shape of Urethral Tissue Engineering." International Journal of Molecular Sciences 20, no. 7 (2019): 1763. http://dx.doi.org/10.3390/ijms20071763.
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Several congenital and acquired conditions may result in severe narrowing of the urethra in men, which represent an ongoing surgical challenge and a significant burden on both health and quality of life. In the field of urethral reconstruction, tissue engineering has emerged as a promising alternative to overcome some of the limitations associated with autologous tissue grafts. In this direction, preclinical as well as clinical studies, have shown that degradable scaffolds are able to restore the normal urethral architecture, supporting neo-vascularization and stratification of the tissue. While a wide variety of degradable biomaterials are under scrutiny, such as decellularized matrices, natural, and synthetic polymers, the search for scaffold materials that could fulfill the clinical performance requirements continues. In this article, we discuss the design requirements of the scaffold that appear to be crucial to better resemble the structural, physical, and biological properties of the native urethra and are expected to support an adequate recovery of the urethral function. In this context, we review the biological performance of the degradable polymers currently applied for urethral reconstruction and outline the perspectives on novel functional polymers, which could find application in the design of customized urethral constructs.
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Kuo, Wen-Shuo, Chia-Yuan Chang, Keng-Shiang Huang, et al. "Amino-Functionalized Nitrogen-Doped Graphene-Quantum-Dot-Based Nanomaterials with Nitrogen and Amino-Functionalized Group Content Dependence for Highly Efficient Two-Photon Bioimaging." International Journal of Molecular Sciences 21, no. 8 (2020): 2939. http://dx.doi.org/10.3390/ijms21082939.
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We fabricated nanomaterials comprising amino-functionalized and nitrogen-doped graphene quantum dots (amino-N-GQDs) and investigated their photostability and intrinsic luminescence in the near-infrared spectrum to determine their suitability as contrast agents in two-photon imaging (TPI). We observed that amino-N-GQDs with a higher amount of bonded nitrogen and amino-functionalized groups (6.2%) exhibited superior two-photon properties to those with a lower amount of such nitrogen and groups (4.9%). These materials were conjugated with polymers containing sulfur (polystyrene sulfonate, PSS) and nitrogen atoms (polyethylenimine, PEI), forming amino-N-GQD–PSS–PEI specimens (amino-N-GQD-polymers). The polymers exhibited a high quantum yield, remarkable stability, and notable two-photon properties and generated no reactive oxygen species, rendering them excellent two-photon contrast agents for bioimaging. An antiepidermal growth factor receptor (AbEGFR) was used for labeling to increase specificity. Two-photon imaging (TPI) of amino-N-GQD (6.2%)-polymer-AbEGFR-treated A431 cancer cells revealed remarkable brightness, intensity, and signal-to-noise ratios for each observation at a two-photon excitation power of 16.9 nJ pixel−1 under 30 scans and a three-dimensional (3D) depth of 105 µm, indicating that amino-N-GQD (6.2%)-polymer-AbEGFR-treated cells can achieve two-photon luminescence with 71 times less power required for two-photon autofluorescence (1322.8 nJ pixel−1 with 500 scans) of similar intensity. This economy can minimize photodamage to cells, rendering amino-N-GQD-polymers suitable for noninvasive 3D bioimaging.
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Czarnecka, Elżbieta, and Jacek Nowaczyk. "Synthesis and Characterization Superabsorbent Polymers Made of Starch, Acrylic Acid, Acrylamide, Poly(Vinyl Alcohol), 2-Hydroxyethyl Methacrylate, 2-Acrylamido-2-methylpropane Sulfonic Acid." International Journal of Molecular Sciences 22, no. 9 (2021): 4325. http://dx.doi.org/10.3390/ijms22094325.
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Three polymers with excellent absorption properties were synthesized by graft polymerization: soluble starch-g-poly(acrylic acid-co-2-hydroxyethyl methacrylate), poly(vinyl alcohol)/potato starch-g-poly(acrylic acid-co-acrylamide), poly(vinyl alcohol)/potato starch-g-poly(acrylic acid-co-acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid). Ammonium persulfate and potassium persulfate were used as initiators, while N,N′-methylenebisacrylamide was used as the crosslinking agent. The molecular structure of potato and soluble starch grafted by synthetic polymers was characterized by means of Fourier Transform Infrared Spectroscopy (FTIR). The morphology of the resulting materials was studied using a scanning electron microscope (SEM). Thermal stability was tested by thermogravimetric measurements. The absorption properties of the obtained biopolymers were tested in deionized water, sodium chroma solutions of various concentrations and in buffer solutions of various pH.
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Toong, Daniel Wee Yee, Han Wei Toh, Jaryl Chen Koon Ng, et al. "Bioresorbable Polymeric Scaffold in Cardiovascular Applications." International Journal of Molecular Sciences 21, no. 10 (2020): 3444. http://dx.doi.org/10.3390/ijms21103444.
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Advances in material science and innovative medical technologies have allowed the development of less invasive interventional procedures for deploying implant devices, including scaffolds for cardiac tissue engineering. Biodegradable materials (e.g., resorbable polymers) are employed in devices that are only needed for a transient period. In the case of coronary stents, the device is only required for 6–8 months before positive remodelling takes place. Hence, biodegradable polymeric stents have been considered to promote this positive remodelling and eliminate the issue of permanent caging of the vessel. In tissue engineering, the role of the scaffold is to support favourable cell-scaffold interaction to stimulate formation of functional tissue. The ideal outcome is for the cells to produce their own extracellular matrix over time and eventually replace the implanted scaffold or tissue engineered construct. Synthetic biodegradable polymers are the favoured candidates as scaffolds, because their degradation rates can be manipulated over a broad time scale, and they may be functionalised easily. This review presents an overview of coronary heart disease, the limitations of current interventions and how biomaterials can be used to potentially circumvent these shortcomings in bioresorbable stents, vascular grafts and cardiac patches. The material specifications, type of polymers used, current progress and future challenges for each application will be discussed in this manuscript.
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Mangal, Utkarsh, Jae-Sung Kwon, and Sung-Hwan Choi. "Bio-Interactive Zwitterionic Dental Biomaterials for Improving Biofilm Resistance: Characteristics and Applications." International Journal of Molecular Sciences 21, no. 23 (2020): 9087. http://dx.doi.org/10.3390/ijms21239087.
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Biofilms are formed on surfaces inside the oral cavity covered by the acquired pellicle and develop into a complex, dynamic, microbial environment. Oral biofilm is a causative factor of dental and periodontal diseases. Accordingly, novel materials that can resist biofilm formation have attracted significant attention. Zwitterionic polymers (ZPs) have unique features that resist protein adhesion and prevent biofilm formation while maintaining biocompatibility. Recent literature has reflected a rapid increase in the application of ZPs as coatings and additives with promising outcomes. In this review, we briefly introduce ZPs and their mechanism of antifouling action, properties of human oral biofilms, and present trends in anti-biofouling, zwitterionic, dental materials. Furthermore, we highlight the existing challenges in the standardization of biofilm research and the future of antifouling, zwitterated, dental materials.
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Puosi, Francesco, Antonio Tripodo, and Dino Leporini. "Fast Vibrational Modes and Slow Heterogeneous Dynamics in Polymers and Viscous Liquids." International Journal of Molecular Sciences 20, no. 22 (2019): 5708. http://dx.doi.org/10.3390/ijms20225708.
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Many systems, including polymers and molecular liquids, when adequately cooled and/or compressed, solidify into a disordered solid, i.e., a glass. The transition is not abrupt, featuring progressive decrease of the microscopic mobility and huge slowing down of the relaxation. A distinctive aspect of glass-forming materials is the microscopic dynamical heterogeneity (DH), i.e., the presence of regions with almost immobile particles coexisting with others where highly mobile ones are located. Following the first compelling evidence of a strong correlation between vibrational dynamics and ultraslow relaxation, we posed the question if the vibrational dynamics encodes predictive information on DH. Here, we review our results, drawn from molecular-dynamics numerical simulation of polymeric and molecular glass-formers, with a special focus on both the breakdown of the Stokes–Einstein relation between diffusion and viscosity, and the size of the regions with correlated displacements.
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Mousavi, Seyyed Mojtaba, Seyyed Alireza Hashemi, Sonia Bahrani, et al. "Recent Advancements in Polythiophene-Based Materials and Their Biomedical, Geno Sensor and DNA Detection." International Journal of Molecular Sciences 22, no. 13 (2021): 6850. http://dx.doi.org/10.3390/ijms22136850.
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In this review, the unique properties of intrinsically conducting polymer (ICP) in biomedical engineering fields are summarized. Polythiophene and its valuable derivatives are known as potent materials that can broadly be applied in biosensors, DNA, and gene delivery applications. Moreover, this material plays a basic role in curing and promoting anti-HIV drugs. Some of the thiophene’s derivatives were chosen for different experiments and investigations to study their behavior and effects while binding with different materials and establishing new compounds. Many methods were considered for electrode coating and the conversion of thiophene to different monomers to improve their functions and to use them for a new generation of novel medical usages. It is believed that polythiophenes and their derivatives can be used in the future as a substitute for many old-fashioned ways of creating chemical biosensors polymeric materials and also drugs with lower side effects yet having a more effective response. It can be noted that syncing biochemistry with biomedical engineering will lead to a new generation of science, especially one that involves high-efficiency polymers. Therefore, since polythiophene can be customized with many derivatives, some of the novel combinations are covered in this review.
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Acevedo-Del-Castillo, Angel, Ernesto Águila-Toledo, Santiago Maldonado-Magnere, and Héctor Aguilar-Bolados. "A Brief Review on the High-Energy Electromagnetic Radiation-Shielding Materials Based on Polymer Nanocomposites." International Journal of Molecular Sciences 22, no. 16 (2021): 9079. http://dx.doi.org/10.3390/ijms22169079.
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This paper revises the use of polymer nanocomposites to attenuate high-energy electromagnetic radiation (HE-EMR), such as gamma radiation. As known, high-energy radiation produces drastic damage not only in facilities or electronic devices but also to life and the environment. Among the different approaches to attenuate the HE-EMR, we consider the use of compounds with a high atomic number (Z), such as lead, but as known, lead is toxic. Therefore, different works have considered low-toxicity post-transitional metal-based compounds, such as bismuth. Additionally, nanosized particles have shown higher performance to attenuate HE-EMR than those that are micro-sized. On the other hand, materials with π-conjugated systems can also play a role in spreading the energy of electrons ejected as a consequence of the interaction of HE-EMR with matter, preventing the ionization and bond scission of polymers. The different effects produced by the interactions of the matter with HE-EMR are revised. The increase of the shielding properties of lightweight, flexible, and versatile materials such as polymer-based materials can be a contribution for developing technologies to obtain more efficient materials for preventing the damage produced for the HE-EMR in different industries where it is found.
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Chi, Minghan, Manlin Qi, Lan A, et al. "Novel Bioactive and Therapeutic Dental Polymeric Materials to Inhibit Periodontal Pathogens and Biofilms." International Journal of Molecular Sciences 20, no. 2 (2019): 278. http://dx.doi.org/10.3390/ijms20020278.
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Periodontitis is a common infectious disease characterized by loss of tooth-supporting structures, which eventually leads to tooth loss. The heavy burden of periodontal disease and its negative consequence on the patient’s quality of life indicate a strong need for developing effective therapies. According to the World Health Organization, 10–15% of the global population suffers from severe periodontitis. Advances in understanding the etiology, epidemiology and microbiology of periodontal pocket flora have called for antibacterial therapeutic strategies for periodontitis treatment. Currently, antimicrobial strategies combining with polymer science have attracted tremendous interest in the last decade. This review focuses on the state of the art of antibacterial polymer application against periodontal pathogens and biofilms. The first part focuses on the different polymeric materials serving as antibacterial agents, drug carriers and periodontal barrier membranes to inhibit periodontal pathogens. The second part reviews cutting-edge research on the synthesis and evaluation of a new generation of bioactive dental polymers for Class-V restorations with therapeutic effects. They possess antibacterial, acid-reduction, protein-repellent, and remineralization capabilities. In addition, the antibacterial photodynamic therapy with polymeric materials against periodontal pathogens and biofilms is also briefly described in the third part. These novel bioactive and therapeutic polymeric materials and treatment methods have great potential to inhibit periodontitis and protect tooth structures.
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Vigneswari, Sevakumaran, Muhammad Shahrul Md Noor, Tan Suet May Amelia, et al. "Recent Advances in the Biosynthesis of Polyhydroxyalkanoates from Lignocellulosic Feedstocks." Life 11, no. 8 (2021): 807. http://dx.doi.org/10.3390/life11080807.
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Polyhydroxyalkanoates (PHA) are biodegradable polymers that are considered able to replace synthetic plastic because their biochemical characteristics are in some cases the same as other biodegradable polymers. However, due to the disadvantages of costly and non-renewable carbon sources, the production of PHA has been lower in the industrial sector against conventional plastics. At the same time, first-generation sugar-based cultivated feedstocks as substrates for PHA production threatens food security and considerably require other resources such as land and energy. Therefore, attempts have been made in pursuit of suitable sustainable and affordable sources of carbon to reduce production costs. Thus, in this review, we highlight utilising waste lignocellulosic feedstocks (LF) as a renewable and inexpensive carbon source to produce PHA. These waste feedstocks, second-generation plant lignocellulosic biomass, such as maize stoves, dedicated energy crops, rice straws, wood chips, are commonly available renewable biomass sources with a steady supply of about 150 billion tonnes per year of global yield. The generation of PHA from lignocellulose is still in its infancy, hence more screening of lignocellulosic materials and improvements in downstream processing and substrate pre-treatment are needed in the future to further advance the biopolymer sector.
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Setayeshmehr, Mohsen, Shahzad Hafeez, Clemens van Blitterswijk, Lorenzo Moroni, Carlos Mota, and Matthew B. Baker. "Bioprinting Via a Dual-Gel Bioink Based on Poly(Vinyl Alcohol) and Solubilized Extracellular Matrix towards Cartilage Engineering." International Journal of Molecular Sciences 22, no. 8 (2021): 3901. http://dx.doi.org/10.3390/ijms22083901.
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Various hydrogel systems have been developed as biomaterial inks for bioprinting, including natural and synthetic polymers. However, the available biomaterial inks, which allow printability, cell viability, and user-defined customization, remains limited. Incorporation of biological extracellular matrix materials into tunable synthetic polymers can merge the benefits of both systems towards versatile materials for biofabrication. The aim of this study was to develop novel, cell compatible dual-component biomaterial inks and bioinks based on poly(vinyl alcohol) (PVA) and solubilized decellularized cartilage matrix (SDCM) hydrogels that can be utilized for cartilage bioprinting. In a first approach, PVA was modified with amine groups (PVA-A), and mixed with SDCM. The printability of the PVA-A/SDCM formulations cross-linked by genipin was evaluated. On the second approach, the PVA was functionalized with cis-5-norbornene-endo-2,3-dicarboxylic anhydride (PVA-Nb) to allow an ultrafast light-curing thiol-ene cross-linking. Comprehensive experiments were conducted to evaluate the influence of the SDCM ratio in mechanical properties, water uptake, swelling, cell viability, and printability of the PVA-based formulations. The studies performed with the PVA-A/SDCM formulations cross-linked by genipin showed printability, but poor shape retention due to slow cross-linking kinetics. On the other hand, the PVA-Nb/SDCM showed good printability. The results showed that incorporation of SDCM into PVA-Nb reduces the compression modulus, enhance cell viability, and bioprintability and modulate the swelling ratio of the resulted hydrogels. Results indicated that PVA-Nb hydrogels containing SDCM could be considered as versatile bioinks for cartilage bioprinting.
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Shilova, Olga, Elena Shramova, Galina Proshkina, and Sergey Deyev. "Natural and Designed Toxins for Precise Therapy: Modern Approaches in Experimental Oncology." International Journal of Molecular Sciences 22, no. 9 (2021): 4975. http://dx.doi.org/10.3390/ijms22094975.
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Cancer cells frequently overexpress specific surface receptors providing tumor growth and survival which can be used for precise therapy. Targeting cancer cell receptors with protein toxins is an attractive approach widely used in contemporary experimental oncology and preclinical studies. Methods of targeted delivery of toxins to cancer cells, different drug carriers based on nanosized materials (liposomes, nanoparticles, polymers), the most promising designed light-activated toxins, as well as mechanisms of the cytotoxic action of the main natural toxins used in modern experimental oncology, are discussed in this review. The prospects of the combined therapy of tumors based on multimodal nanostructures are also discussed.
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Kim, Bonglee, Ji-Eon Park, Eunji Im, et al. "Recent Advances in Nanotechnology with Nano-Phytochemicals: Molecular Mechanisms and Clinical Implications in Cancer Progression." International Journal of Molecular Sciences 22, no. 7 (2021): 3571. http://dx.doi.org/10.3390/ijms22073571.
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Biocompatible nanoparticles (NPs) containing polymers, lipids (liposomes and micelles), dendrimers, ferritin, carbon nanotubes, quantum dots, ceramic, magnetic materials, and gold/silver have contributed to imaging diagnosis and targeted cancer therapy. However, only some NP drugs, including Doxil® (liposome-encapsulated doxorubicin), Abraxane® (albumin-bound paclitaxel), and Oncaspar® (PEG-Asparaginase), have emerged on the pharmaceutical market to date. By contrast, several phytochemicals that were found to be effective in cultured cancer cells and animal studies have not shown significant efficacy in humans due to poor bioavailability and absorption, rapid clearance, resistance, and toxicity. Research to overcome these drawbacks by using phytochemical NPs remains in the early stages of clinical translation. Thus, in the current review, we discuss the progress in nanotechnology, research milestones, the molecular mechanisms of phytochemicals encapsulated in NPs, and clinical implications. Several challenges that must be overcome and future research perspectives are also described.
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d'Ischia, Marco, Paola Manini, Marco Moracci, et al. "Astrochemistry and Astrobiology: Materials Sciencein Wonderland?" International Journal of Molecular Sciences 20, no. 17 (2019): 4079. http://dx.doi.org/10.3390/ijms20174079.
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Astrochemistry and astrobiology, the fascinating disciplines that strive to unravel the origin of life, have opened unprecedented and unpredicted vistas into exotic compounds as well as extreme or complex reaction conditions of potential relevance for a broad variety of applications. Representative, and so far little explored sources of inspiration include complex organic systems, such as polycyclic aromatic hydrocarbons (PAHs) and their derivatives; hydrogen cyanide (HCN) and formamide (HCONH2) oligomers and polymers, like aminomalononitrile (AMN)-derived species; and exotic processes, such as solid-state photoreactions on mineral surfaces, phosphorylation by minerals, cold ice irradiation and proton bombardment, and thermal transformations in fumaroles. In addition, meteorites and minerals like forsterite, which dominate dust chemistry in the interstellar medium, may open new avenues for the discovery of innovative catalytic processes and unconventional methodologies. The aim of this review was to offer concise and inspiring, rather than comprehensive, examples of astrochemistry-related materials and systems that may be of relevance in areas such as surface functionalization, nanostructures, and hybrid material design, and for innovative technological solutions. The potential of computational methods to predict new properties from spectroscopic data and to assess plausible reaction pathways on both kinetic and thermodynamic grounds has also been highlighted.
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Alam, Todd M., Joshua P. Allers, and Brad H. Jones. "Heterogeneous Polymer Dynamics Explored Using Static 1H NMR Spectra." International Journal of Molecular Sciences 21, no. 15 (2020): 5176. http://dx.doi.org/10.3390/ijms21155176.
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NMR spectroscopy continues to provide important molecular level details of dynamics in different polymer materials, ranging from rubbers to highly crosslinked composites. It has been argued that thermoset polymers containing dynamic and chemical heterogeneities can be fully cured at temperatures well below the final glass transition temperature (Tg). In this paper, we described the use of static solid-state 1H NMR spectroscopy to measure the activation of different chain dynamics as a function of temperature. Near Tg, increasing polymer segmental chain fluctuations lead to dynamic averaging of the local homonuclear proton-proton (1H-1H) dipolar couplings, as reflected in the reduction of the NMR line shape second moment (M2) when motions are faster than the magnitude of the dipolar coupling. In general, for polymer systems, distributions in the dynamic correlation times are commonly expected. To help identify the limitations and pitfalls of M2 analyses, the impact of activation energy or, equivalently, correlation time distributions, on the analysis of 1H NMR M2 temperature variations is explored. It is shown by using normalized reference curves that the distributions in dynamic activation energies can be measured from the M2 temperature behavior. An example of the M2 analysis for a series of thermosetting polymers with systematically varied dynamic heterogeneity is presented and discussed.
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Uchida, Noriyuki, and Takahiro Muraoka. "Current Progress in Cross-Linked Peptide Self-Assemblies." International Journal of Molecular Sciences 21, no. 20 (2020): 7577. http://dx.doi.org/10.3390/ijms21207577.
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Peptide-based fibrous supramolecular assemblies represent an emerging class of biomaterials that can realize various bioactivities and structures. Recently, a variety of peptide fibers with attractive functions have been designed together with the discovery of many peptide-based self-assembly units. Cross-linking of the peptide fibers is a key strategy to improve the functions of these materials. The cross-linking of peptide fibers forming three-dimensional networks in a dispersion can lead to changes in physical and chemical properties. Hydrogelation is a typical change caused by cross-linking, which makes it applicable to biomaterials such as cell scaffold materials. Cross-linking methods, which have been conventionally developed using water-soluble covalent polymers, are also useful in supramolecular peptide fibers. In the case of peptide fibers, unique cross-linking strategies can be designed by taking advantage of the functions of amino acids. This review focuses on the current progress in the design of cross-linked peptide fibers and their applications.
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Marques-Almeida, Teresa, Vanessa F. Cardoso, Miguel Gama, Senentxu Lanceros-Mendez, and Clarisse Ribeiro. "Patterned Piezoelectric Scaffolds for Osteogenic Differentiation." International Journal of Molecular Sciences 21, no. 21 (2020): 8352. http://dx.doi.org/10.3390/ijms21218352.
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The morphological clues of scaffolds can determine cell behavior and, therefore, the patterning of electroactive polymers can be a suitable strategy for bone tissue engineering. In this way, this work reports on the influence of poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) electroactive micropatterned scaffolds on the proliferation and differentiation of bone cells. For that, micropatterned P(VDF-TrFE) scaffolds were produced by lithography in the form of arrays of lines and hexagons and then tested for cell proliferation and differentiation of pre-osteoblast cell line. Results show that more anisotropic surface microstructures promote bone differentiation without the need of further biochemical stimulation. Thus, the combination of specific patterns with the inherent electroactivity of materials provides a promising platform for bone regeneration.
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Cataldo, Franco. "On the Optical Activity of Poly(l-lactic acid) (PLLA) Oligomers and Polymer: Detection of Multiple Cotton Effect on Thin PLLA Solid Film Loaded with Two Dyes." International Journal of Molecular Sciences 22, no. 1 (2020): 8. http://dx.doi.org/10.3390/ijms22010008.
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Optical rotatory dispersion (ORD) is a beautiful analytical technique for the study of chiral molecules and polymers. In this study, ORD was applied successfully to follow the degree of polycondensation of l-(+)-lactic acid toward the formation of poly(lactic acid) oligomers (PLAO) and high molecular weight poly(l-lactic acid) (PLLA) in a simple esterification reaction equipment. PLLA is a biodegradable polymer obtainable from renewable raw materials. The racemization of the intrinsically isotactic PLLA through thermal treatment can be easily followed through the use of ORD spectroscopy. Organic or molecular electronics is a hot topic dealing with the combination of π-conjugated organic compounds and polymers with specific properties (e.g., chirality) which can be exploited to construct optoelectronic devices, such as organic light-emitting diodes (OLEDs), organic photovoltaic (OPV) high efficiency cells, switchable chirality devices, organic field-effect transistors (OFETs), and so on. ORD spectroscopy was applied to study either the gigantic optical rotation of PLLA films, as well as to detect successfully the excitonic coupling, occurring in thin solid PLLA green film loaded with a combination of two dyes: SY96 (a pyrazolone dye) and PB16 (the metal-free phthalocyanine pigment). The latter compound PLLA loaded with SY96 and PB16 shows a really gigantic optical activity in addition to typical ORD signal due to exciton coupling and may be considered as a simple and easily accessible model composite of a chiral polymer matrix combined with π-conjugated dyes for molecular electronics studies.
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De Santis, Felice, and Roberto Pantani. "Optical Properties of Polypropylene upon Recycling." Scientific World Journal 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/354093.
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In the last few years there has been an increasing interest in the possibility of recycling polymeric materials, using physical recycling. However, is it well known that polymers experience a depletion of all the properties upon recycling. These effects have been widely characterized in the literature for what concerns the mechanical or rheological properties. The changes of optical properties after recycling have been much less studied, even if, especially in food packaging, optical characteristics (above all the opacity) are of extreme importance, and thus it is quite significant to assess the effect of recycling on these properties. In this work, the influence of recycling steps on the opacity of films of a commercial grade of isotactic polypropylene (i-PP) was studied. The material was extruded several times to mimic the effect of recycling procedures. After extrusion, films were obtained by cooling samples of material at different cooling rates. The opacity of the obtained films was then measured and related to their crystallinity and morphology. It was found that opacity generally increases on increasing the amount ofαphase and for the same amount ofαphase on increasing the size of the spherulites.
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Lainioti, Georgia C., Anthi Tsapikouni, Denisa Druvari, et al. "Environmentally Friendly Cross-Linked Antifouling Coatings Based on Dual Antimicrobial Action." International Journal of Molecular Sciences 22, no. 9 (2021): 4658. http://dx.doi.org/10.3390/ijms22094658.
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The synthesis of environmentally friendly antimicrobial polymeric coatings, especially in the case of aquaculture, that inhibit the growth of bio-deposits is a very important issue that will contribute to the cost reduction of nets’ cleaning process as well as the protection of the submarine wealth from the biostatic substances used so far. In the present work, the antimicrobial polymers P(SSAmC16-co-VBCHAMx) and the terpolymer P(SSAmC16w-co-VBCHAMx-co-GMAy) were synthesized, bearing quaternary ammonium compounds, electrostatically bound and covalently attached at the same polymer chain. The combination of the two types is of particular importance, as it can provide effective antimicrobial polymeric materials with self-polishing capabilities as a result of the released nature of the antimicrobial, in combination with the permanent local action of the immobilized species. The cross-linking reaction of the terpolymer P(SSAmC16w-co-VBCHAMx-co-GMAy) with the homopolymer polyacrylic acid (PAA) was tested at 120 °C in terms of the equivalent ratio between epoxy and carboxyl groups. The synthesized polymers were further used for the coating of aquaculture nets and tested in terms of antifouling efficiency in lab and scale-up conditions. Uncoated nets were also used in all applications for comparison reasons. The coated nets performed efficiently for 35 days in lab-scale and 66 days in scale-up conditions, showing a high antifouling activity in both fields compared to the uncoated nets.
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Racovita, Stefania, Marin-Aurel Trofin, Diana Felicia Loghin, et al. "Polybetaines in Biomedical Applications." International Journal of Molecular Sciences 22, no. 17 (2021): 9321. http://dx.doi.org/10.3390/ijms22179321.
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Polybetaines, that have moieties bearing both cationic (quaternary ammonium group) and anionic groups (carboxylate, sulfonate, phosphate/phosphinate/phosphonate groups) situated in the same structural unit represent an important class of smart polymers with unique and specific properties, belonging to the family of zwitterionic materials. According to the anionic groups, polybetaines can be divided into three major classes: poly(carboxybetaines), poly(sulfobetaines) and poly(phosphobetaines). The structural diversity of polybetaines and their special properties such as, antifouling, antimicrobial, strong hydration properties and good biocompatibility lead to their use in nanotechnology, biological and medical fields, water remediation, hydrometallurgy and the oil industry. In this review we aimed to highlight the recent developments achieved in the field of biomedical applications of polybetaines such as: antifouling, antimicrobial and implant coatings, wound healing and drug delivery systems.
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Yavuz, Burçin, Sibel Bozdağ Pehlivan, and Nurşen Ünlü. "Dendrimeric Systems and Their Applications in Ocular Drug Delivery." Scientific World Journal 2013 (2013): 1–13. http://dx.doi.org/10.1155/2013/732340.
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Ophthalmic drug delivery is one of the most attractive and challenging research area for pharmaceutical scientists and ophthalmologists. Absorption of an ophthalmic drug in conventional dosage forms is seriously limited by physiological conditions. The use of nonionic or ionic biodegradable polymers in aqueous solutions and colloidal dosage forms such as liposomes, nanoparticles, nanocapsules, microspheres, microcapsules, microemulsions, and dendrimers has been studied to overcome the problems mentioned above. Dendrimers are a new class of polymeric materials. The unique nanostructured architecture of dendrimers has been studied to examine their role in delivery of therapeutics and imaging agents. Dendrimers can enhance drug’s water solubility, bioavailability, and biocompatibility and can be applied for different routes of drug administration successfully. Permeability enhancer properties of dendrimers were also reported. The use of dendrimers can also reduce toxicity versus activity and following an appropriate application route they allow the delivery of the drug to the targeted site and provide desired pharmacokinetic parameters. Therefore, dendrimeric drug delivery systems are of interest in ocular drug delivery. In this review, the limitations related to eye’s unique structure, the advantages of dendrimers, and the potential applications of dendrimeric systems to ophthalmology including imaging, drug, peptide, and gene delivery will be discussed.
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Zyuzin, Mikhail V., Dingcheng Zhu, Wolfgang J. Parak, Neus Feliu, and Alberto Escudero. "Development of Silica-Based Biodegradable Submicrometric Carriers and Investigating Their Characteristics as in Vitro Delivery Vehicles." International Journal of Molecular Sciences 21, no. 20 (2020): 7563. http://dx.doi.org/10.3390/ijms21207563.
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Nanostructured silica (SiO2)-based materials are attractive carriers for the delivery of bioactive compounds into cells. In this study, we developed hollow submicrometric particles composed of SiO2 capsules that were separately loaded with various bioactive molecules such as dextran, proteins, and nucleic acids. The structural characterization of the reported carriers was conducted using transmission and scanning electron microscopies (TEM/SEM), confocal laser scanning microscopy (CLSM), and dynamic light scattering (DLS). Moreover, the interaction of the developed carriers with cell lines was studied using standard viability, proliferation, and uptake assays. The submicrometric SiO2-based capsules loaded with DNA plasmid encoding green fluorescence proteins (GFP) were used to transfect cell lines. The obtained results were compared with studies made with similar capsules composed of polymers and show that SiO2-based capsules provide better transfection rates on the costs of higher toxicity.
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Battafarano, Giulia, Michela Rossi, Viviana De Martino, et al. "Strategies for Bone Regeneration: From Graft to Tissue Engineering." International Journal of Molecular Sciences 22, no. 3 (2021): 1128. http://dx.doi.org/10.3390/ijms22031128.
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Bone is a regenerative organ characterized by self-renewal ability. Indeed, it is a very dynamic tissue subjected to continuous remodeling in order to preserve its structure and function. However, in clinical practice, impaired bone healing can be observed in patients and medical intervention is needed to regenerate the tissue via the use of natural bone grafts or synthetic bone grafts. The main elements required for tissue engineering include cells, growth factors and a scaffold material to support them. Three different materials (metals, ceramics, and polymers) can be used to create a scaffold suitable for bone regeneration. Several cell types have been investigated in combination with biomaterials. In this review, we describe the options available for bone regeneration, focusing on tissue engineering strategies based on the use of different biomaterials combined with cells and growth factors.
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Nemcakova, Ivana, Lucie Blahova, Petr Rysanek, Andreu Blanquer, Lucie Bacakova, and Lenka Zajíčková. "Behaviour of Vascular Smooth Muscle Cells on Amine Plasma-Coated Materials with Various Chemical Structures and Morphologies." International Journal of Molecular Sciences 21, no. 24 (2020): 9467. http://dx.doi.org/10.3390/ijms21249467.
Full textAbstract:
Amine-coated biodegradable materials based on synthetic polymers have a great potential for tissue remodeling and regeneration because of their excellent processability and bioactivity. In the present study, we have investigated the influence of various chemical compositions of amine plasma polymer (PP) coatings and the influence of the substrate morphology, represented by polystyrene culture dishes and polycaprolactone nanofibers (PCL NFs), on the behavior of vascular smooth muscle cells (VSMCs). Although all amine-PP coatings improved the initial adhesion of VSMCs, 7-day long cultivation revealed a clear preference for the coating containing about 15 at.% of nitrogen (CPA-33). The CPA-33 coating demonstrated the ideal combination of good water stability, a sufficient amine group content, and favorable surface wettability and morphology. The nanostructured morphology of amine-PP-coated PCL NFs successfully slowed the proliferation rate of VSMCs, which is essential in preventing restenosis of vascular replacements in vivo. At the same time, CPA-33-coated PCL NFs supported the continuous proliferation of VSMCs during 7-day long cultivation, with no significant increase in cytokine secretion by RAW 264.7 macrophages. The CPA-33 coating deposited on biodegradable PCL NFs therefore seems to be a promising material for manufacturing small-diameter vascular grafts, which are still lacking on the current market.
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Shang, Xiaoqin, Huihua Jiang, Qingling Wang, Peng Liu, and Fengwei Xie. "Cellulose-starch Hybrid Films Plasticized by Aqueous ZnCl2 Solution." International Journal of Molecular Sciences 20, no. 3 (2019): 474. http://dx.doi.org/10.3390/ijms20030474.
Full textAbstract:
Starch and cellulose are two typical natural polymers from plants that have similar chemical structures. The blending of these two biopolymers for materials development is an interesting topic, although how their molecular interactions could influence the conformation and properties of the resultant materials has not been studied extensively. Herein, the rheological properties of cellulose/starch/ZnCl2 solutions were studied, and the structures and properties of cellulose-starch hybrid films were characterized. The rheological study shows that compared with starch (containing mostly amylose), cellulose contributed more to the solution’s viscosity and has a stronger shear-thinning behavior. A comparison between the experimental and calculated zero-shear-rate viscosities indicates that compact complexes (interfacial interactions) formed between cellulose and starch with ≤50 wt % cellulose content, whereas a loose structure (phase separation) existed with ≥70 wt % cellulose content. For starch-rich hybrid films prepared by compression molding, less than 7 wt % of cellulose was found to improve the mechanical properties despite the reduced crystallinity of the starch; for cellulose-rich hybrid films, a higher content of starch reduced the material properties, although the chemical interactions were not apparently influenced. It is concluded that the mechanical properties of biopolymer films were mainly affected by the structural conformation, as indicated by the rheological results.