Articoli di riviste: "Ca-alginate"

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Dianawati, Dianawati, Vijay Mishra e Nagendra P. Shah. "Role of Calcium Alginate and Mannitol in Protecting Bifidobacterium". Applied and Environmental Microbiology 78, n. 19 (27 luglio 2012): 6914–21. http://dx.doi.org/10.1128/aem.01724-12.

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ABSTRACTFourier transform infrared (FTIR) spectroscopy was carried out to ascertain the mechanism of Ca-alginate and mannitol protection of cell envelope components and secondary proteins ofBifidobacterium animalissubsp.lactisBb12 after freeze-drying and after 10 weeks of storage at room temperature (25°C) at low water activities (aw) of 0.07, 0.1, and 0.2. Preparation of Ca-alginate and Ca-alginate-mannitol as microencapsulants was carried out by dropping an alginate or alginate-mannitol emulsion containing bacteria using a burette into CaCl2solution to obtain Ca-alginate beads and Ca-alginate-mannitol beads, respectively. The wet beads were then freeze-dried. The awof freeze-dried beads was then adjusted to 0.07, 0.1, and 0.2 using saturated salt solutions; controls were prepared by keeping Ca-alginate and Ca-alginate-mannitol in aluminum foil without awadjustment. Mannitol in the Ca-alginate system interacted with cell envelopes during freeze-drying and during storage at low aws. In contrast, Ca-alginate protected cell envelopes after freeze-drying but not during 10-week storage. Unlike Ca-alginate, Ca-alginate-mannitol was effective in retarding the changes in secondary proteins during freeze-drying and during 10 weeks of storage at low aws. It appears that Ca-alginate-mannitol is more effective than Ca-alginate in preserving cell envelopes and proteins after freeze-drying and after 10 weeks of storage at room temperature (25°C).

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Petzold, Guillermo, María Pia Gianelli, Graciela Bugueño, Raymond Celan, Constanza Pavez e Patricio Orellana. "Encapsulation of liquid smoke flavoring in ca-alginate and ca-alginate-chitosan beads". Journal of Food Science and Technology 51, n. 1 (9 luglio 2013): 183–90. http://dx.doi.org/10.1007/s13197-013-1090-z.

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Machida-Sano, Ikuko, Sakito Ogawa, Makoto Hirakawa e Hideo Namiki. "Evaluation of Three-Dimensional Porous Iron-Cross-Linked Alginate as a Scaffold for Cell Culture". ISRN Biomaterials 2014 (6 febbraio 2014): 1–6. http://dx.doi.org/10.1155/2014/375758.

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We investigated the efficacy of three-dimensional porous ferric-ion-cross-linked alginate (Fe-alginate) gels as cell scaffolds, in comparison with calcium-ion-cross-linked alginate (Ca-alginate) gels. In a previous study, we had demonstrated that two-dimensional Fe-alginate film was an efficient material for use as a scaffold, allowing good cell adhesion and proliferation, unlike Ca-alginate film. In the present study, we fabricated three-dimensional porous Fe- and Ca-alginate gels by freeze-drying and evaluated their effects on cultured cells. The Fe-alginate gels showed higher protein adsorption ability than Ca-alginate gels. Cells formed multicellular spheroids in both types of alginate scaffold, but the number of cultured cells increased with culture time on Fe-alginate porous gels, whereas those on Ca-alginate gels did not. Moreover, it was revealed that the cells on Fe-alginate scaffolds were still viable inside the multicellular spheroids even after cultivation for 14 days. These results suggest that Fe-alginate provides a superior porous scaffold suitable for three-dimensional culture of cells. Our findings may be useful for extending the application of Fe-alginate to diverse biomedical fields.

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Meng, Zhi-Jun, Wei Wang, Rui Xie, Xiao-Jie Ju, Zhuang Liu e Liang-Yin Chu. "Microfluidic generation of hollow Ca-alginate microfibers". Lab on a Chip 16, n. 14 (2016): 2673–81. http://dx.doi.org/10.1039/c6lc00640j.

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Controllable hollow Ca-alginate microfibers are continuously fabricated from microfluidic four-aqueous-phase flow templates, which contain a buffer flow between Ca²⁺ and alginate flows for prevention of rapid Ca²⁺/alginate crosslinking.

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Truong, Vinh. "Release kinetics of lime essential oil (Citrus aurantifolia) from beads microencapsulated through ion-gel method". Journal of Agriculture and Development 20, n. 1 (26 febbraio 2021): 58–66. http://dx.doi.org/10.52997/jad.8.01.2021.

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Ca-Alginate beads for microencapsulation of lime oil (Citrus aurantifolia) by ion-gel method was manufactured and then soaked in Chitosan solution to obtain Ca-Alginate-Chitosan beads. Increased CaCl2 concentrations reduced lime essential oil release. The alginate concentration (2 to 3%) and water temperature significantly affected the release of oil (P < 0.05). The higher temperatures, the higher the release rate. The oil release at 75oC was twice as much as at 45oC. At 45oC, the difference in the release rate among the alginate concentrations of 2%, 2.5% and 3% was clear and statistically significant (P < 0.05). However, at 60oC and 75oC, there was no significant difference in release between the alginate concentration of 2.5% and 3% (P > 0.05). In the storage of beads in 1% CaCl2 solution at normal temperature, after the first 15 days, Ca Alginate-Chitosan system released about 3% slower than Ca-Alginate system, but there was no difference between the two systems after 45 days. This shows that if prolonged for a long time, the ion-gelation of Ca-Alginate prevails over the Alginate-Chitosan cross-link.

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Paraskevopoulou, Patrina, Grigorios Raptopoulos, Faidra Leontaridou, Maria Papastergiou, Aikaterini Sakellari e Sotirios Karavoltsos. "Evaluation of Polyurea-Crosslinked Alginate Aerogels for Seawater Decontamination". Gels 7, n. 1 (4 marzo 2021): 27. http://dx.doi.org/10.3390/gels7010027.

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Polyurea-crosslinked Ca-alginate (X-Ca-alginate) aerogel beads (diameter: 3.3 mm) were evaluated as adsorbents of metal ions, organic solvents, and oils. They were prepared via reaction of an aromatic triisocyanate (Desmodur RE) with pre-formed Ca-alginate wet gels and consisted of 54% polyurea and 2% calcium. X-Ca-alginate aerogels are hydrophobic nanoporous materials (90% v/v porosity), with a high BET surface area (459 m2/g−1), and adsorb PbII not only from ultrapure water (29 mg/g−1) but also from seawater (13 mg/g−1) with high selectivity. The adsorption mechanism involves replacement of CaII by PbII ions coordinated to the carboxylate groups of the alginate backbone. After treatment with a Na2EDTA solution, the beads can be reused, without significant loss of activity for at least two times. X-Ca-alginate aerogels can also uptake organic solvents and oil from seawater; the volume of the adsorbate can be as high as the total pore volume of the aerogel (6.0 mL/g−1), and the absorption is complete within seconds. X-Ca alginate aerogels are suitable for the decontamination of aquatic environments from a broader range of inorganic and organic pollutants.

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Peng, Li, Jia Ni Huan, Jing Hua Gong e Jing Hong Ma. "Preparation and Characterization of Stimuli-Responsive Poly(N-Isopropylacrylamide)/Ca-Alginate Hydrogel Fiber by Microfluidic Spinning". Materials Science Forum 898 (giugno 2017): 2360–65. http://dx.doi.org/10.4028/www.scientific.net/msf.898.2360.

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Smart hydrogel is a kind of new soft and wet material which can be responsive to external stimuli. Hydrogel fiber owning one dimension size can significantly improve response speed and be easily formed into higher-order assemblies. N-isopropylacrylamide/calcium alginate (NIPA/Ca-alginate) as-spun fiber was generated via microfluidic spinning. Then PNIPA/Ca-alginate hydrogel fiber was prepared through off-chip free radical polymerization of NIPA in the presence of Ca-alginate. The structure and morphology of the hydrogel fiber were characterized by FTIR and SEM. The swelling property and temperature-/pH-response behaviors were also investigated. The PNIPA/Ca-alginate hydrogel fiber had a 3D network porous structure. The thinner the hydrogel fiber, the faster the swelling speed was. Meanwhile, the hydrogel fiber exhibited temperature and pH response.

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Wibowo, Agung Ari, Ade Sonya Suryandari, Eko Naryono, Vania Mitha Pratiwi, Muhammad Suharto e Naila Adiba. "Encapsulation of Clove Oil within Ca-Alginate-Gelatine Complex: Effect of Process Variables on Encapsulation Efficiency". Jurnal Teknik Kimia dan Lingkungan 5, n. 1 (29 aprile 2021): 71. http://dx.doi.org/10.33795/jtkl.v5i1.214.

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Karena memiliki khasiat seperti analgesik, minyak cengkeh biasa digunakan sebagai obat, antibakteri, antioksidan, dan antimikroba. Kemungkinan enkapsulasi minyak cengkeh sebagai makrokapsul padat dipelajari dengan pembuatan makrokapsul Ca-Alginate-Gelatine. Variabel proses yang digunakan adalah variasi konsentrasi alginat 1% dan 1,5% b / v, dan perbandingan massa antara alginat-gelatin divariasikan antara 1: 4, 1: 6, dan 1: 8 w /w. Selain itu, variasi konsentrasi CaCl2 (10%, 20% dan 30% w / v) sebagai cross-linking agent pembentukan kompleks Ca-Alginate juga digunakan sebagai variabel proses. Peningkatan konsentrasi alginat, gelatin dan CaCl2 nampaknya menurunkan efisiensi enkapsulasi karena terbatasnya volume ruang bebas yang terbentuk pada matriks Ca-Alginat-Gelatin. Efisiensi enkapsulasi tertinggi (93,08%) diperoleh pada penggunaan Alginat 1% w / v, dengan perbandingan alginat dengan gelatin 1: 4 dan ikatan silang dalam larutan CaCl2 10% w / v selama 15 menit.Owing to the properties such as analgesic, clove oil is commonly used as medicine, antibacterial, antioxidant, and antimicrobial drugs. The possibility of clove oil encapsulation as a solid macrocapsule was studied by making Ca-Alginate-Gelatine macrocapsules. The process variables used were variations in Alginate concentration of 1% and 1.5% w/v, and the mass ratio between alginate-gelatine was varied between 1: 4, 1: 6, and 1: 8 w/w. In addition, variations in the concentration of CaCl2 (10%, 20% and 30% w/v) as a cross-linking agent for the formation of Ca-Alginate complexes were also used as process variables. The increase of alginate, gelatine and CaCl2 concentration seems to decreased the encapsulation efficiency because of the limitation of the free space volume formed in the Ca-Alginate-Gelatine matrix. The highest encapsulation efficiency (93.08%) was obtained in the use of Alginate 1% w/v, with a ratio of alginate to gelatine 1: 4 and cross-linking in a 10% w/v CaCl2 solution for 15 minutes.

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Bediako, John Kwame, Myung Hee Song e Yeoung Sang Yun. "Fabrication and Application of Polyethylenimine/Ca-Alginate Blended Hydrogel Fibers as High-Capacity Adsorbents for Recovery of Gold from Acidic Solutions". Solid State Phenomena 262 (agosto 2017): 103–6. http://dx.doi.org/10.4028/www.scientific.net/ssp.262.103.

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High-capacity polyethylenimine (PEI)/Ca-alginate blended hydrogel fibers were fabricated via three steps, viz. electrostatic blending of PEI and alginate, ionotropic gelation of alginate and CaCl2, and fixing of PEI into the Ca-alginate matrix, using glutaraldehyde (GA) as a crosslinker. Two crosslinking approaches resulted in different stabilities and gold uptake capacities of the prepared sorbents. Post-crosslinking approach was more efficient than pre-crosslinking likely owing to the better crosslinking efficiency, leading to better stability and sorption capacity. Furthermore, X-ray diffraction (XRD) study revealed the reduction of Au (III) to metallic gold, Au (0) in the crosslinked fibers. The Au (0) predominancy was confirmed with a metal desorption study. The present study thus demonstrates the possibility of recovering metallic gold from aqueous solutions by direct adsorption-coupled-reduction approach using GA-crosslinked PEI/Ca-alginate fibers.

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Xu, Feng Lan, Yu Bao Li, Jimei Han e Guo Yu Lv. "Biodegradable Porous Nano-Hydroxyapatite/Alginate Scaffold". Materials Science Forum 486-487 (giugno 2005): 189–92. http://dx.doi.org/10.4028/www.scientific.net/msf.486-487.189.

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Porous scaffold containing biodegradable Ca-crosslinked alginate(ALG) and nano-hydroxyapatite(n-HA) is synthesized by the freeze-extraction and freeze-gelation methods. The prepared scaffolds were tested by scanning electron microscopy (SEM), transmission electron microscopy (TEM), infrared absorption spectra (IR), raman spectra, X-ray diffraction (XRD) and burning test. Chemical binding between inorganic n-HA and Ca-crosslinked alginate was investigated. It indicated that n-HA was interacted with Ca-crosslinked alginate. The results of SEM showed that the scaffolds exhibited open-cellular pore structures. The content of n-HA affected the porosity and pore size of the composite. The composite can be a promising scaffold material for tissue engineering.

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Ahmed, Husnain, e Bjørn Torger Stokke. "Fabrication of monodisperse alginate microgel beads by microfluidic picoinjection: a chelate free approach". Lab on a Chip 21, n. 11 (2021): 2232–43. http://dx.doi.org/10.1039/d1lc00111f.

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Monodisperse microgel beads are fabricated by injecting chelate free aqueous Ca²⁺ in aqueous Na-alginate emulsion and vice versa. This method of producing alginate microbeads without reducing activity of Ca²⁺ is significant for biological assays.

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Kollár, Mariann, Gabriella Zsoldos e Tamás Szabó. "UHMWPE Modified Sodium Alginate". Materials Science Forum 812 (febbraio 2015): 101–6. http://dx.doi.org/10.4028/www.scientific.net/msf.812.101.

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Aim of our experiments was to modify prosthetic material UHMWPE powder using sodium alginate. The sodium alginate has an important property that the appropriate chemical reagent could exchange its Na+ions to Ca2+ions. The Ca has important role in the healing process, so modifying this substance the UHMWPE material helps patients healing. In the first step we examined that the raw material UHMWPE powder is necessary to be treated in order to adhere alginate at the surface of the UHMWPE powder. In a second step, we examined that insoluble Ca alginate coating left at the surface of UHMWPE powder after the exchange of Na ions. The treated powders were analyzed by Fourier Transformed Infrared Spectroscopy and Diffential Scanning Calorymetry methods. SEM investigations were carried out on the prepared samples moreover energy-dispersive X-ray spectroscopy (EDAX) measurements were performed,-for detection of the presence of small amounts of Na and Ca ions. It has been found that the complex and complicated Caro’s acid chemical treatment is unnecessary in order to prepare alginate coated substrates. The best results were achieved by selecting the correct order of surface layer preparation; first coating the substrate with alginate solution then treating with aqueous CaCl2.

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Wang, Xiao Hua. "Research and Option in the Preparation of PVA-Alginate-Ca". Applied Mechanics and Materials 189 (luglio 2012): 176–80. http://dx.doi.org/10.4028/www.scientific.net/amm.189.176.

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Based on the index of water content, the influence of the dosage of glutaraldehyde, the mass ratio of polyvinyl alcohol(PVA) and alginate(NaAlg), the concentration of CaCl2, and the reaction time on PVA-alginate-Ca was discussed. It can be found that when the dosage of glutaraldehyde is 0.85%, the mass ration of PVA increases to 8:1, the solution quality score of CaCl2 is 2%, and the reaction time of PVA-alginate-Ca is 1.5h, the composite polymer water content reaches the highest.Then the preparation condition for PVA-alginate-Ca will be optimized by an orthogonal experiment design, and the optimum preparation condition will be found: ω (glutaraldehyde) is 0.85%, m（PVA）:m（NaAlg）is 8:1 andω(CaCl2)is 2.0%.

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Zhang, Yahui, Xiaoyan Lin, Hongyan Liu, Yuanyuan Qu e Xuegang Luo. "Preparation and characterization of a core–shell KNO3@alginate-Ca particle with uranium-removal and slow-release of KNO3". RSC Advances 6, n. 113 (2016): 112065–78. http://dx.doi.org/10.1039/c6ra23307d.

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A novel core–shell KNO₃@alginate-Ca particle was prepared by a facile method of electro-coextrusion. The core–shell KNO₃@alginate-Ca particle was a promising adsorbent for uranium removal and a slow-release material for potassium release.

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Huang, Dan Lian, Guang Ming Zeng, Piao Xu, Cui Lai, Mei Hua Zhao, Chao Huang, Ning Jie Li, Chen Zhang, Fang Ling Li e Min Cheng. "Application of Immobilized Fungi Phanerochaete chrysosporium in Removal of Heavy-Metals from Wastewater". Advanced Materials Research 779-780 (settembre 2013): 1674–77. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.1674.

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Immobilized microbe technologies are expected to be effectively used in wastewater treatment. Removal of heavy-metals from wastewater by immobilized Phanerochaete chrysosporium (Pc) with Ca-alginate and iron oxide magnetic nanoparticles (MNPs) was studied. The results showed that a biosorbent as Pc immobilized by Ca-alginate and iron oxide magnetic nanoparticles was successfully developed. And the iron oxide magnetic nanoparticles played an important role in the increase of biosorption capacity of Pc. Energy dispersive spectrometer (EDS) analysis confirmed that metal ions adsorbed to the surface of the biosorbents were partly transmitted to the interior of biosorbents, mainly embedded with iron oxide nanoparticles and Ca-alginate. Moreover, it was found that MNPs-Ca-alginate immobilized Pc showed a good affinity to various heavy metals, such as Pb(II), Zn(II), Cd(II) or Mg(II) and so on. The results proved the high efficiency of the biosorbents for heavy-metal removal and its potential application in the treatment of metal-containing wastewater.

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Park, S. B., H. W. Kang, S. Haam, H. Y. Park e W. S. Kim. "Ca-alginate microspheres encapsulated in chitosan beads". Journal of Microencapsulation 21, n. 5 (agosto 2004): 485–97. http://dx.doi.org/10.1080/02652040410001729269.

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TOMIDA, Hisao, Chikara MIZUO, Chie NAKAMURA e Setsuo KIRYU. "Imipramine Release from Ca-Alginate Gel Beads." CHEMICAL & PHARMACEUTICAL BULLETIN 41, n. 8 (1993): 1475–77. http://dx.doi.org/10.1248/cpb.41.1475.

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Sletmoen, Marit, Kurt I. Draget e Bjørn T. Stokke. "Alginate Oligoguluronates as a Tool for Tailoring Properties of Ca-Alginate Gels". Macromolecular Symposia 291-292, n. 1 (8 giugno 2010): 345–53. http://dx.doi.org/10.1002/masy.201050541.

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Abbah, S. A., W. W. Lu, S. L. Peng, D. M. K. Aladin, Z. Y. Li, W. K. Tam, K. M. C. Cheung, K. D. K. Luk e Guang-Qian Zhou. "Extracellular Matrix Stability of Primary Mammalian Chondrocytes and Intervertebral Disc Cells Cultured in Alginate-Based Microbead Hydrogels". Cell Transplantation 17, n. 10-11 (ottobre 2008): 1181–92. http://dx.doi.org/10.3727/096368908787236648.

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Three-dimensional alginate constructs are widely used as carrier systems for transplantable cells. In the present study, we evaluated the chondrogenic matrix stability of primary rat chondrocytes and intervertebral disc (IVD) cells cultured in three different alginate-based microbead matrices to determine the influence of microenvironment on the cellular and metabolic behaviors of chondrogenic cells confined in alginate microbeads. Cells entrapped in calcium, strontium, or barium ion gelled microbeads were monitored with the live/dead dual fluorescent cell viability assay kit and the 1,9-dimethylmethylene blue (DMB) assay designed to evaluate sulfated glycosaminoglycan (s-GAG) production. Expression of chondrogenic extracellular matrix (ECM) synthesis was further evaluated by semiquantitative RT-PCR of sox9, type II collagen, and aggrecan mRNAs. Results indicate that Ca and Sr alginate maintained significantly higher population of living cells compared to Ba alginate (p < 0.05). Production of s-GAG was similarly higher in Ca and Sr alginate microbead cultures compared to Ba alginate microbeads. Although there was no significant difference between strontium and calcium up to day 14 of culture, Sr alginate showed remarkably improved cellular and metabolic activities on long-term cultures, with chondrocytes expressing as much as 31% and 44% greater s-GAG compared to calcium and barium constructs, respectively, while IVD cells expressed 63% and 74% greater s-GAG compared to calcium and barium constructs, respectively, on day 28. These findings indicate that Sr alginate represent a significant improvement over Ca- and Ba alginate microbeads for the maintenance of chondrogenic phenotype of primary chondrocytes and IVD cells.

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Hutchinson, Ucrecia F., Seteno K. O. Ntwampe, Boredi S. Chidi, Maxwell Mewa-Ngongang, Heinrich W. du Plessis, Mardé Booyse e Neil P. Jolly. "Reusability of Immobilized Cells for Subsequent Balsamic-Styled Vinegar Fermentations". Fermentation 6, n. 4 (29 ottobre 2020): 103. http://dx.doi.org/10.3390/fermentation6040103.

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Cell immobilization is a process augmentation technique aimed at improving microbial survival and activity under stressful conditions. It offers the opportunity to reuse the immobilized cells for several fermentation cycles. The present study investigated the use of recycled cells entrapped in calcium-alginate beads and cells adsorbed on corncobs (CC) and oakwood chips (OWC) in subsequent fermentation cycles for balsamic-styled vinegar (BSV) production. Sugars, pH, alcohol and total acidity were monitored during fermentation. Microbial activity and product formation declined when immobilized cells were reused for the second cycle for CC and OWC fermentations. Recycled cells entrapped in Ca-alginate beads completed the second cycle of fermentations, albeit at reduced acetification rates compared to the first cycle. Scanning electron microscope (SEM) imaging results further showed a substantial the structural integrity loss for Ca-alginate beads after the first cycle, and with minor changes in the structural integrity of CC. The OWC displayed a similar morphological structure before and after the first cycle. The sensory results showed that BSV produced using immobilized cells with Ca-alginate beads and CC was palatable, while those produced using OWC had negative attributes. Ca-alginate beads offered better protection for the fermentation consortium for culture reusability in BSV fermentations.

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Zhao, Kongyin, Ning Gao, Chao Liu e Guoxiang Cheng. "Molecularly-Imprinted Calcium Phosphate/Calcium Alginate Composite Microspheres by Surface Imprinting via Silane Crosslinking". Adsorption Science & Technology 26, n. 8 (ottobre 2008): 631–41. http://dx.doi.org/10.1260/026361708788059857.

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This paper describes the development of a new type of molecularly-imprinted composite microspheres. Composite microspheres of calcium phosphate/calcium alginate (CP/CA CMs) were prepared from calcium phosphate and sodium alginate through the use of calcium chloride (CaCl2) as a gelling agent in an inverse suspension. Molecularly-imprinted calcium phosphate/calcium alginate composite microspheres (CP/CA MICMs) were then prepared by surface imprinting using CP/CA CMs as the supporting matrix, ethylene tri(β-methoxy)ethoxysilane (A-172) and γ-amidopropyltriethoxysilane (KH-550) as the functional monomers and crosslinking agents, respectively, and Methyl Orange as the template in aqueous solution. The CP/CA MICMs and non-imprinted composite microspheres (NICMs) were characterized by Fourier-transform infrared spectroscopy and optical microscopy. The adsorption behaviour of the CP/CA MICMs and NICMs were determined by ultraviolet spectrophotometry. The results indicated that molecular imprinting occurs via the crosslinking of silanes on the surface of the CP/CA CMs, and that CP/CA MICMs possess an adsorption capacity which exhibits greater selectivity. A schematic representation of the imprinting and recognition process of CA/CP MICMs by surface imprinting via silane crosslinking was presented.

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Hanifah, Sarina, Rusnadi Rusnadi e M. Bachri Amran. "Coffee Biomass Encapsulated in Calcium Alginate as Material for Lead (II) Adsorption from Aqueous Solutions". Journal of Pure and Applied Chemistry Research 10, n. 1 (14 aprile 2021): 72–83. http://dx.doi.org/10.21776/ub.jpacr.2021.010.01.577.

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This work aims to study the removal of lead (II) from aqueous solutions with Ca-Alginate (CA) and Coffee-Calcium-Alginate (CCA). The coffee biomass were successfully prepared as the material to be encapsulated in calcium alginate. The characterization of the synthesized CA and CCA was performed using fourier transform infrared and scanning electron microscopy. The method used was batch study. Various factors which affected adsorption efficiency of lead (II) ions by CA and CCA, such as pH, agitation time, and adsorbent dose were investigated for determination of optimum experimental conditions. The result showed that CA and CCA had significant effects on adsorption of lead (ІІ) ions at pH = 4, agitation time of more than 120 min, and the adsorbent dose was 0.05 gram. Moreover, the Langmuir isotherm model showed that maximum adsorption capacity (qm) was 163.66 mg/g and 176.99 mg/g respectively for CA and CCA. The Langmuir isotherm was better described the adsorption equilibrium. Both of the adsorbent fitted to pseudo second order equations. These results demonstrated that CA and CCA show great potential to remove Pb(ІІ) ions from aqueous solutions.

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Demey, Barron-Zambrano, Mhadhbi, Miloudi, Yang, Ruiz e Sastre. "Boron Removal from Aqueous Solutions by Using a Novel Alginate-Based Sorbent: Comparison with Al2O3 Particles". Polymers 11, n. 9 (16 settembre 2019): 1509. http://dx.doi.org/10.3390/polym11091509.

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Boron removal was evaluated in the present work by using calcium alginate beads (CA) and a novel composite based on alginate–alumina (CAAl) as sorbents in a batch system. The effects of different parameters such as pH, temperature, contact time, and composition of alginate (at different concentrations of guluronic and mannuronic acids) on boron sorption were investigated. The results confirm that calcium alginate beads (CA) exhibited a better adsorption capacity in a slightly basic medium, and the composite alginate–alumina (CAAl) exhibited improved boron removal at neutral pH. Sorption isotherm studies were performed and the Langmuir isotherm model was found to fit the experimental data. The maximum sorption capacities were 4.5 mmol g−1 and 5.2 mmol g−1, using CA and CAAl, respectively. Thermodynamic parameters such as change in free energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) were also determined. The pseudo-first-order and pseudo-second-order rate equations (PFORE and PSORE, respectively) were tested to fit the kinetic data; the experimental results can be better described with PSORE. The regeneration of the loaded sorbents was demonstrated by using dilute HCl solution (distilled water at pH 3) as eluent for metal recovery.

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Wang, Yaolei, Lei Zhao, Chang Tian, Chao Ma e Jinyi Wang. "Geometrically controlled preparation of various cell aggregates by droplet-based microfluidics". Analytical Methods 7, n. 23 (2015): 10040–51. http://dx.doi.org/10.1039/c5ay02466h.

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Torres-Caban, Roberto, Carmen A. Vega-Olivencia e Nairmen Mina-Camilde. "Adsorption of Ni2+ and Cd2+ from Water by Calcium Alginate/Spent Coffee Grounds Composite Beads". Applied Sciences 9, n. 21 (25 ottobre 2019): 4531. http://dx.doi.org/10.3390/app9214531.

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The use of heavy metals in technological applications has led to detrimental effects on human health and the environment. Activated carbon and ion-exchange resins are commonly used to remove pollutants but they are expensive. Therefore, the research of low-cost alternatives derived from natural resources and organic wastes is being considered. The aim of this study considers the use of Calcium Alginate/Spent Coffee Grounds (CA–SCGs) composite beads to adsorb heavy metals from aqueous solutions, particularly, the removal of Ni2+ or Cd2+ at concentrations from 10 ppm to 100 ppm. CA–SCGs beads were made of equal proportions of alginate and spent coffee grounds and compared with calcium alginate beads (CA beads) and spent coffee grounds (SCGs) in terms of capacity and rate of adsorption. Three cycles of adsorption/desorption were done. The beads were characterized by Scanning Electron Microscopy coupled with an energy-dispersive X-ray spectroscopy (SEM–EDX), Fourier-transform infrared spectroscopy (FT–IR), Raman spectroscopy, and point of zero charge. Langmuir, Freundlich, and Sips models, and a pseudo-second-order kinetic equation were used. Sips model showed the best correlation with the adsorption of CA–SCGs beads with capacities of adsorption of 91.18 mg/g for cadmium and 20.96 mg/g for nickel. CA–SCGs beads had a greater adsorption than the CA beads, achieving adsorption percentages close to 100% than alginate alone, showing their effectiveness in heavy metal removal.

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Sáenz-Santos, Christian Mariel, Omotayo Opemipo Oyedara, Yunia Verónica García-Tejeda, Claudia A. Romero-Bastida, Esperanza Milagros García-Oropesa, Eduardo Villalobo e Mario A. Rodríguez-Pérez. "Active Biopolymeric Films Inoculated with Bdellovibrio bacteriovorus, a Predatory Bacterium". Coatings 11, n. 5 (20 maggio 2021): 605. http://dx.doi.org/10.3390/coatings11050605.

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The objective of the present work was to evaluate novel active films made with biopolymeric matrices as carriers of a living Bdellovibrio bacteriovorus HD100 strain, a predatory bacterium with antimicrobial potentials against pathogens. Biopolymer films were prepared by a casting method using the following mixtures: collagen/sodium alginate/sorbitol (CA-S), collagen/sodium alginate/glycerol (CA-G), and tapioca starch/sodium alginate/glycerol (StA-G). The effects of the film formulations on the viability of the B. bacteriovorus was investigated by using Fourier Transform Infrared (FTIR) spectroscopy, Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM). SEM showed that Bdellovibrio bacteriovorus morphology was not altered in the polymeric films. FTIR spectroscopy provided information about the structural composition of the films. CA-S showed less reduction in the viability of B. bacteriovorus after its entrapment; thus, CA-S proved to be a better agent for the immobilization and preservation of B. bacteriovorus to enhance its predatory activities during application against Escherichia coli.

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Monbouquette, H. G., e D. F. Ollis. "Scanning Microfluorimetry of Ca-Alginate Immobilized Zymomonas Mobilis". Nature Biotechnology 6, n. 9 (settembre 1988): 1076–79. http://dx.doi.org/10.1038/nbt0988-1076.

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MIURA, YOSHIHARU, NORIKO YOSHIKAWA, TOSHIHIKO AKIMOTO e KIYOHITO YAGI. "Therapeutic Effect of Hepatocytes Entrapped within Ca-Alginate". Annals of the New York Academy of Sciences 613, n. 1 Enzyme Engine (dicembre 1990): 475–78. http://dx.doi.org/10.1111/j.1749-6632.1990.tb18203.x.

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Istenič, Katja, Bojana D. Balanč, Verica B. Djordjević, Marjan Bele, Viktor A. Nedović, Branko M. Bugarski e Nataša Poklar Ulrih. "Encapsulation of resveratrol into Ca-alginate submicron particles". Journal of Food Engineering 167 (dicembre 2015): 196–203. http://dx.doi.org/10.1016/j.jfoodeng.2015.04.007.

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Chen, Sha, Jing Hua Gong e Jing Hong Ma. "Microfluidic Fabrication of Helical Ca-Alginate Hydrogel Fibers". Materials Science Forum 1035 (22 giugno 2021): 843–50. http://dx.doi.org/10.4028/www.scientific.net/msf.1035.843.

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Helix is a sophisticated structure in nature and has many unique functions which makes it possible to store more information and energy, even receive more sensitive signals. Besides, as an effective method for preparing hydrogel fibers, microfluidic spinning has achieved unprecedented development in the past decade. However, hydrogel fiber with helical structure has began to be studied only in recent years. In this paper, the helical hydrogel fibers were prepared by the microfluidic spinning method. The microfluidic chip was assembled by PDMS connector, collection tube, inner and outer channels. Sodium alginate (SA) and calcium chloride were used as the core fluid and sheath fluid, respectively. By designing and adjusting the length of the chip, changing the concentration of SA and the ratio of two flow rates (inner flow rate/outer flow rate), a continuous and uniform helical hydrogel fiber was prepared. The relationships between the diameter of the fiber, the pitch of the helix and the concentration of SA, the ratio of two flow rates were discussed. The results showed that the diameter of the fiber was mainly affected by the core fluid. Within a certain range, as the concentration of SA increased, the diameter of the fiber increased. Besides, the pitch of the helix was greatly affected by the flow rate of sheath fluid. As the velocity of the sheath fluid increased, the pitch of the fiber increased. Such helical fiber could be used in micro sensors when added some conductive materials or crosslinked with some temperature responsive polymers such as N-isopropylacrylamide.

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Torres-Caban, Roberto, Carmen Vega-Olivencia, Luis Alamo-Nole, Daisy Morales-Irizarry, Felix Roman-Velazquez e Nairmen Mina-Camilde. "Removal of Copper from Water by Adsorption with Calcium-Alginate/Spent-Coffee-Grounds Composite Beads". Materials 12, n. 3 (27 gennaio 2019): 395. http://dx.doi.org/10.3390/ma12030395.

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Calcium Alginate/Spent-Coffee-Grounds composite beads (CA-SCGs beads), which were made of two different proportions of alginate and spent-coffee-grounds (3:3 and 3:10), respectively, were used to adsorb Cu2+ in aqueous solution. These beads were compared with calcium alginate beads (CA beads) and spent-coffee-grounds (SCGs) in terms of adsorption capacity and rate of adsorption. The experiments were carried out at an initial pH of 4 at 30 °C with initial concentrations of Cu2+ from 10 ppm to 100 ppm. Equilibrium data was fitted with Langmuir, Freundlich and Sips models, and a pseudo-second-order kinetic equation. The Sips model showed the best correlation with the experimental values. CA-SCGs (3:3) beads showed a faster adsorption rate versus the CA beads. Also, CA-SCGs (3:3) beads showed a larger capacity of adsorption according to the Sips model, but not in the Langmuir model. FT-IR spectra and SEM images were taken for characterization. This study has shown that the CA-SCGs (3:3) beads have a synergistic effect, combining the capacity of adsorption of CA beads with the kinetics of the SCGs. The CA-SCGs beads have proven to be an effective adsorbent of Cu2+. Therefore, they can provide a use for the SCGs; which are considered pollutants in landfills.

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JIANG, JIANFANG, HAIXIN CUI e YU CAO. "PREPARATION AND PROPERTY STUDIES OF Zn3P2/CALCIUM ALGINATE". Nano 09, n. 02 (febbraio 2014): 1450014. http://dx.doi.org/10.1142/s1793292014500143.

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Zn 3 P 2 is an acute and effective rodenticide used widely to protect grains in stores and domestically to kill rodents. This study aims to postpone the time of poisoning symptoms after eating Zn 3 P 2 and improve the effect of killing rodents. Zn 3 P 2/calcium alginate ( Zn 3 P 2/ CA ) was synthesized through the reaction of sodium alginate and calcium chloride by the reversed-phase microemulsion method and then loaded with Zn 3 P 2 technical. It was characterized by X-ray diffractometer, laser particle size analyzer, scanning electron microscope (SEM) and transmission electron microscopy (TEM). The drug loading capacity, slow-controlled release performances and toxic effects were also investigated. The results showed that Zn 3 P 2/ CA was spherical, average particle size was 353.9 nm, and particle dispersion index (PDI) was 0.195. The mass ratios of calcium alginate and Zn 3 P 2 technical ( CA / Zn 3 P 2) had significant impacts to drug loading capacity and slow-controlled release performances of Zn 3 P 2/ CA . The palatability and efficacy of Zn 3 P 2/ CA were significantly improved and enhanced compared with Zn 3 P 2 technical. The results showed that Zn 3 P 2/ CA presented high loading efficiency, commendable sustained-release performance and good environmental compatibility, and this delivery carrier may be extended to other slow-controlled release and high-efficient pesticide formulation in future.

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Pan, Linhai, Zhuqing Wang, Qi Yang e Rongyi Huang. "Efficient Removal of Lead, Copper and Cadmium Ions from Water by a Porous Calcium Alginate/Graphene Oxide Composite Aerogel". Nanomaterials 8, n. 11 (20 novembre 2018): 957. http://dx.doi.org/10.3390/nano8110957.

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In this study, we fabricated a porous calcium alginate/graphene oxide composite aerogel by using polystyrene colloidal particles as sacrificial template and graphene oxide as a reinforcing filler. Owing to the excellent metal chelation ability of calcium alginate and controlled nanosized pore structure, the as-prepared calcium alginate/graphene oxide composite aerogel (mp-CA/GO) can reach the adsorption equilibrium in 40 min, and the maximum adsorption capacity for Pb2+, Cu2+ and Cd2+ is 368.2, 98.1 and 183.6 mg/g, respectively. This is higher than most of the reported heavy metal ion sorbents. Moreover, the mp-CA/GO can be regenerated through simple acid-washing and be used repeatedly with little loss in performance. The adsorption mechanism analysis indicates that the mp-CA/GO adsorb the heavy metal ions mainly through the ion exchange and chemical coordination effects.

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Carter-Fenk, Kimberly A., Abigail C. Dommer, Michelle E. Fiamingo, Jeongin Kim, Rommie E. Amaro e Heather C. Allen. "Calcium bridging drives polysaccharide co-adsorption to a proxy sea surface microlayer". Physical Chemistry Chemical Physics 23, n. 30 (2021): 16401–16. http://dx.doi.org/10.1039/d1cp01407b.

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Alginate co-adsorbs to a proxy sea surface microlayer palmitate film via Ca²⁺-mediated ionic bridging interactions between alginate and palmitate carboxylate groups. This mechanism provides evidence for polysaccharide enrichment in marine aerosol.

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Dalheim, Marianne Ø., Line Aa Omtvedt, Isabel M. Bjørge, Anita Akbarzadeh, João F. Mano, Finn L. Aachmann e Berit L. Strand. "Mechanical Properties of Ca-Saturated Hydrogels with Functionalized Alginate". Gels 5, n. 2 (19 aprile 2019): 23. http://dx.doi.org/10.3390/gels5020023.

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In this work, the mechanical properties and stability of alginate hydrogels containing functionalized alginates (peptide and β-cyclodextrin) were studied. There is an increasing interest in the modification of alginates to add functions such as cell attachment and increased solubility of hydrophobic drugs, for better performance in tissue engineering and drug release, respectively. Functionalization was achieved in this study via periodate oxidation followed by reductive amination, previously shown to give a high and controllable degree of substitution. Young’s modulus and the stress at rupture of the hydrogels were in general lowered when exchanging native alginate with the modified alginate. Still, the gel strength could be adjusted by the fraction of modified alginate in the mixed hydrogels as well as the degree of oxidation. No notable difference in deformation at rupture was observed while syneresis was influenced by the degree of oxidation and possibly by the nature and amount of the grafted molecules. The mixed hydrogels were less stable than hydrogels with only native alginate, and modified alginate was released from the hydrogels. Furthermore, the hydrogels in general rather disintegrated than swelled upon saline treatments.

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Essifi, Kamal, Mohamed Brahmi, Doha Berraaouan, Abderrahim Ed-Daoui, Ali El Bachiri, Marie-Laure Fauconnier e Abdesselam Tahani. "Influence of Sodium Alginate Concentration on Microcapsules Properties Foreseeing the Protection and Controlled Release of Bioactive Substances". Journal of Chemistry 2021 (21 agosto 2021): 1–13. http://dx.doi.org/10.1155/2021/5531479.

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To understand the abilities of Ca-alginate microcapsules and their specific applications in different fields, it is necessary to determine the physicochemical and structural properties of those formulated microcapsules. In this work, we aimed to study the effect of alginate concentration in the improvement of the encapsulation efficiency (EE) and on the release of phenolic and flavonoid substances. The relationship between the structure of the encapsulated bioactive substance and Ca-alginate network and their effect on the EE and release kinetics have been investigated. The incorporation, structure, morphology, and phase properties of all elaborated materials were characterized by UV-spectroscopy, Fourier transform infrared (ATR-FTIR), scanning electron microscope (SEM), and X-ray diffraction (DRX). The results indicate that increasing the polymer concentration increases the EE and decreases the loading capacity (LC), whereas the effect of alginate polymer concentration on the release was not observed. The release study of bioactive substances showed that the release kinetics is relatively dependent on the structure and the physicochemical characteristics of the bioactive substance, which became clear when the encapsulated compounds were released from the core of calcium alginate microcapsules. Thus, it could be concluded that the pores size of the Ca-alginate network is smaller than the volume of the crocin molecule (2794.926 Å3) and higher than the volume of the gallic acid molecule (527.659 Å3). For the same microcapsules system, the release mechanism is affected by the structure and physicochemical properties of the encapsulated molecules.

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Luo, Ming Fang, e Hui Zhou Liu. "Desulfurization of Model Oil Containing Dibenzothiophene or 4,6-Dimethyl Dibenzothiophene by Alginate Immobilized Cells". Advanced Materials Research 233-235 (maggio 2011): 1171–76. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.1171.

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Gram-negative bacterium, Pseudomonas delafieldii R-8 (CGMCC 0570) is capable of desulfurizing dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) to produce corresponding monohydroxydimethylbiphenyl. The immobilization of the resting cells of this strain in Ca-alginate gel effectively improved the stability of the cells and the desulfurization ability per amount of cells. 1 mmol/L of DBT and 4,6-DMDBT could be completely degraded in about 1 d. About 39 percent of the activity for 4,6-DMDBT was recovered after immobilization. The desulfurization activity was increased with the decrease of the diameter of the beads. The Ca-alginate immobilized cells could be used repeatedly for over 190 h with the addition of calcium ions to strengthen them. A thin layer of hydrophobic polyurea was coated on the surface of Ca-alginate gel using a simple method. The desulfurization activity was enhanced after the coating.

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Uzun, Umit, e Melike Yildirim Akatin. "Immobilization and some application of α-amylase purified from Rhizoctonia solani AG-4 strain ZB-34". Turkish Journal of Biochemistry 44, n. 3 (8 gennaio 2019): 397–407. http://dx.doi.org/10.1515/tjb-2018-0240.

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Abstract Background Aim of the study was to immobilize the α-amylase produced earlier from the mesophilic fungus Rhizoctonia solani AG-4 strain ZB-34 by solid-state fermentation and investigate the suitability of immobilized enzymes for some industries. Materials and methods A novel α-amylase from R. solani AG-4 strain ZB-34 was immobilized in chitosan by covalent binding and Ca-alginate by entrapment. Results The efficiency of chitosan and Ca-alginate immobilization was 67.9% and 59.6%, respectively. The immobilized enzymes showed the highest activity in the presence of starch. Optimum values for chitosan and Ca-alginate immobilized enzymes were pH 4.50 and 40°C and pH 5.50 and 60°C, respectively. It was found that immobilized enzymes were highly stable in terms of thermal and pH stabilities. When the chitosan immobilized enzyme was used with detergents, chocolate stains on dirty laundry was better cleaned. Chitosan immobilized R. solani AG-4 strain ZB-34 α-amylase was found to have a higher desizing effect at 40°C in tap water. As a result of Ca-alginate immobilization, the enzyme clarified apple juice more than the free enzyme. Conclusion The results showed that immobilized enzymes might have potential applications in industry. This is the first report immobilizing an α-amylase produced from the fungus R. solani.

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Iskakov, R. M., E. O. Batyrbekov, B. A. Zhubanov, Y. Y. Fomicheva, V. K. Yu, K. D. Praliev e D. K. Berlin. "Immobilization of Analgetic AB-101 into Calcium Alginate Gels". Eurasian Chemico-Technological Journal 4, n. 4 (1 luglio 2017): 293. http://dx.doi.org/10.18321/ectj547.

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A new analgetic drug AB-101 has been immobilized into Ca2+-alginate gel beads with average diameter of 1 mm. A series of the alginate gel contains with various mannuronic/guluronic (M/G) ratios has been chosen to control the diffusion of the drug. Release of the drug from the alginate gel beads into physiological solutions consisting of sodium ions has been examined. A discontinuous time of the Fickian diffusion of the drug depending on M/G ratio was followed by a burst release of the remaining drugs. The burst release was due to a swift disintegration of Ca2+-alginate with exchange on sodium ions. The preceding discontinuous lag time promotes a free dissociate exchange of sodium-calcium ions in M units, while the burst disintegration leads to fast dissociation of G units. The lag time can be control by M/G ratio of Ca2+-alginate gels. The lag time increases if a content of the M units decreases. The increase of M units was led to more extensive swelling of the gel beads. Such way could be promising for a controlled drug delivery or the use in implants with controlled drug effect.

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Liang, Ben-liang, Jian-feng Wang, Ying-qi Shu, Peng-gang Yin e Lin Guo. "A biomimetic ion-crosslinked layered double hydroxide/alginate hybrid film". RSC Advances 7, n. 52 (2017): 32601–6. http://dx.doi.org/10.1039/c7ra04577h.

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Inspired by the structure of nacre, a biomimetic Ca²⁺-crosslinked layered double hydroxide/alginate (LDH/ALG-Ca²⁺) hybrid film is prepared, which exhibits excellent mechanical property and high transparency.

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Zhu, Haotian, Tao Chen, Jingquan Liu e Da Li. "Adsorption of tetracycline antibiotics from an aqueous solution onto graphene oxide/calcium alginate composite fibers". RSC Advances 8, n. 5 (2018): 2616–21. http://dx.doi.org/10.1039/c7ra11964j.

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In this study, we report the preparation of a novel environmentally friendly and highly efficient adsorbent, graphene oxide/calcium alginate (GO/CA) composite fibers, via a freeze-drying method using calcium chloride as a cross-linking reagent between graphene oxide and sodium alginate.

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Fan, Yiang, Yunhai Wu, Peng Fang e Zhu Ming. "Facile and effective synthesis of adsorbent – utilization of yeast cells immobilized in sodium alginate beads for the adsorption of phosphorus in aqueous solution". Water Science and Technology 75, n. 1 (20 ottobre 2016): 75–83. http://dx.doi.org/10.2166/wst.2016.491.

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We compared the adsorption efficiency of phosphates onto Ca-alginate immobilized yeast and freely suspended yeast under different conditions of pH and temperature. The results clearly demonstrated that the adsorption efficiency onto Ca-alginate immobilized yeast was better than that of freely suspended yeast, and reached a maximum at pH 9.17 and 35 °C. Scanning electron microscopy was used to characterize the morphology of Ca-alginate immobilized yeast. Fitting the adsorption equilibrium data to existing models showed that the Freundlich isotherm model described the process better than the Langmuir model, and the process of adsorption followed pseudo-first-order kinetics. During the initial period of experiment, external diffusion was a key rate-controlling step, and intraparticle diffusion also contributed to the mass transport. The thermodynamic properties (Gibbs free energy change of −15.143 kJ/mol, enthalpy change of 274.118 kJ/mol, and entropy change of 290 J/(mol K)) indicated that the adsorption process was endothermic.

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Yu, Chong, Hong Sun e Shifeng Hou. "Direct electrochemistry and electrocatalysis of myoglobin immobilized in calcium alginate–graphene microsphere films". Analytical Methods 9, n. 33 (2017): 4873–81. http://dx.doi.org/10.1039/c7ay01364g.

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In the present work, calcium alginate–graphene (CA–graphene) microspheres have been prepared and used to immobilize myoglobin (Mb) for fabricating electroactive Mb–CA–graphene microsphere thin films on the electrode surface.

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Xie, Han, Yijiao Chen, Can Wang, Wenjin Shi, Lei Zuo e Heng Xu. "The removal of fluoranthene by Agaricus bisporus immobilized in Ca-alginate modified by Lentinus edodes nanoparticles". RSC Advances 5, n. 56 (2015): 44812–23. http://dx.doi.org/10.1039/c5ra04419g.

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Fruiting bodies of Agaricus bisporus (A. bisporus) were entrapped in Ca-alginate modified by Lentinus edodes nanoparticles (CA-LENP) to adsorb and biodegrade fluoranthene (FLU) efficiently from an aqueous solution in a fluidized bed bioreactor.

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Kusumastuti, Yuni, Alit Istiani, Rochmadi e Chandra Wahyu Purnomo. "Chitosan-Based Polyion Multilayer Coating on NPK Fertilizer as Controlled Released Fertilizer". Advances in Materials Science and Engineering 2019 (2 maggio 2019): 1–8. http://dx.doi.org/10.1155/2019/2958021.

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Low efficiency of conventional fertilizer (quick release fertilizer) application in agricultural sectors has caused environmental pollution and health problems. A method to overcome the drawback of the conventional fertilizer is by controlled release fertilizer (CRF) preparation. CRF is expected to be able to fulfil the nutrient demand of targeted plants. The objective of this research is to prepare CRF by coating NPK fertilizer with multilayer chitosan-polyanion using alginate, pectin, and sodium tripolyphosphate (TPP). In addition, the effect of the layer arrangement modification of material on the rate of nitrogen release was also studied. The mechanical strength of coated fertilizer was analysed by compressive stress test and the properties of the fertilizer coating was observed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The nitrogen release study shows that multilayer of chitosan-alginate (CA)5, chitosan-pectin (CP)5, and chitosan-TPP (CT)5 as coating material was able to increase the compressive stress and decrease the nitrogen release of coated fertilizer. These results are supported by the FTIR analysis which exhibits the formation of ionic interaction between amine group of chitosan and carboxyl group of alginate in chitosan-alginate (CA)5 layer, carboxyl group of pectin in chitosan-pectin (CP)5 layer, and phosphate of TPP in chitosan-TPP (CT)5 layer. On the other hand, the modification of the arrangement of chitosan-alginate layers showed that the fertilizer with the alternating layer arrangement (CA)5 was able to optimally increase the compressive strength. The mathematical model for the nitrogen release of coated fertilizer is also prepared and simulated with the MATLAB software. The simulation results showed that the nitrogen release of coated fertilizer followed the proposed diffusion mechanism. The obtained diffusivity coefficient value in the layer of chitosan-alginate (CA)5 is 2.0933 × 10−6 cm2/s, 2.5606 × 10−6 cm2/s in chitosan-TPP (CT)5 layer, and 3.7256 × 10−6 cm2/s in chitosan-pectin (CP)5 layer.

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Müller, Werner E. G., Emad Tolba, Heinz C. Schröder, Meik Neufurth, Shunfeng Wang, Thorben Link, Bilal Al-Nawas e Xiaohong Wang. "A new printable and durable N,O-carboxymethyl chitosan–Ca2+–polyphosphate complex with morphogenetic activity". Journal of Materials Chemistry B 3, n. 8 (2015): 1722–30. http://dx.doi.org/10.1039/c4tb01586j.

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In the absence of Ca²⁺ the polymers N,O-carboxymethyl chitosan, together with Na-polyphosphate and alginate, form random-coiled structures. Addition of Ca²⁺ transforms these polymers to durable implants.

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Zvukova, Natalia D., Tamara P. Klimova, Roman V. Ivanov, Andrei N. Ryabev, Archil V. Tsiskarashvili e Vladimir I. Lozinsky. "Cryostructuring of Polymeric Systems. 52. Properties, Microstructure and an Example of a Potential Biomedical Use of the Wide-Pore Alginate Cryostructurates". Gels 5, n. 2 (9 maggio 2019): 25. http://dx.doi.org/10.3390/gels5020025.

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Wide-pore cryostructurates were prepared via freezing sodium alginate aqueous solutions with subsequent ice sublimation from the frozen samples, followed by their incubation in the ethanol solutions of calcium chloride or sulfuric acid, rinsing, and final drying. Such sequence of operations resulted in the calcium alginate or alginic acid sponges, respectively. The swelling degree of the walls of macropores in such matrices decreased with increasing polymer concentration in the initial solution. The dependence of the degree of swelling on the cryogenic processing temperature had a bell-like character with a maximum for the samples formed at −20 °C. According to 1H NMR spectroscopy, the content of mobile (non-frozen) water in the frozen water-sodium alginate systems also depended on the initial polymer concentration and freezing temperature. The cryostructurates obtained did not lose their integrity in water, saline, in an acidic medium at pH 2 for at least three weeks. Under alkaline conditions at pH 12 the first signs of dissolution of the Ca-alginate sponge arose only after a week of incubation. Microbiological testing of the model depot form of the antibiotics entrapped in the Ca-alginate cryostructurate demonstrated the efficiency of this system as the antibacterial material.

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Finotelli, P. V., D. A. Sampaio, M. A. Morales, A. M. Rossi e M. H. Rocha-Leão. "Ca alginate as scaffold for iron oxide nanoparticles synthesis". Brazilian Journal of Chemical Engineering 25, n. 4 (dicembre 2008): 759–64. http://dx.doi.org/10.1590/s0104-66322008000400013.

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Grizeau, D., e J. M. Navarro. "Glycerol production byDunaliella tertiolecta immobilized within Ca-alginate beads". Biotechnology Letters 8, n. 4 (aprile 1986): 261–64. http://dx.doi.org/10.1007/bf01030509.

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Bashari, Mohanad, Pei Wang, Ahmed Eibaid, Yaoqi Tian, Xueming Xu e Zhengyu Jin. "Ultrasound-assisted dextranase entrapment onto Ca-alginate gel beads". Ultrasonics Sonochemistry 20, n. 4 (luglio 2013): 1008–16. http://dx.doi.org/10.1016/j.ultsonch.2012.11.016.

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