Journal articles: 'PLA-PEG'

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Jeong, Heeseok, Hyunju Lim, Deuk Yong Lee, Yo-Seung Song, and Bae-Yeon Kim. "Preparation and Drug Release Behavior of Nifedipine-Loaded Poly(lactic acid)/Polyethylene Glycol Microcapsules." Journal of Nanoscience and Nanotechnology 21, no. 7 (2021): 3735–41. http://dx.doi.org/10.1166/jnn.2021.19168.

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Nifedipine (NF)-loaded poly(lactic acid) (PLA) and PLA/polyethylene glycol (PLA/PEG) microcapsules are synthesized using a high-speed agitator and a syringe pump with an oil-in-water emulsion-solvent evaporation technique to evaluate the effect of PLA/PEG ratio on morphology and drug release behavior of the capsules. Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimeter (DSC), and X-ray diffraction (XRD) results indicate that PEG reacts successfully with PLA due to the ether bond between PEG and PLA. The drug release rate of PLA and PLA/PEG capsules increases dramatically from 0 to 5 min and then reaches a plateau within 15 to 20 min. Due to the high specific surface area, the amount of NF released is raised by reducing the PLA concentration from 5 wt% to 2 wt%. Unlike PLA capsules, the drug release rate of PLA/PEG capsules increases due to the size effect by varying the PLA/PEG ratio from 10/0 to 6/4. Larger PLA/PEG capsules are attributed to higher amounts of encapsulated NF. The capsules show no evidence of cytotoxicity, suggesting that the PLA and PLA/PEG drug carriers are clinically safe.

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Mohd Asri, Syazeven Effatin Azma, Zainoha Zakaria, Azman Hassan, Mohamad Haafiz Mohamad Kassim, and Reza Arjmandi. "Exploring the Effects of Fermented Chitin Nanowhiskers on Tensile and Thermal Properties of Poly(ethylene glycol) modified Polylactic Acid Nanocomposites." Malaysian Journal of Fundamental and Applied Sciences 17, no. 2 (2021): 154–65. http://dx.doi.org/10.11113/mjfas.v17n2.2002.

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The incorporation of fermented chitin nanowhiskers (FCHW) into poly(lactic acid) (PLA) increased the tensile modulus and strength of PLA at the expense of ductility. The brittleness of PLA can be overcome with the use of plasticizer such as polyethylene glycols (PEG). The objective of this study is to investigate the effect of FCHW on the tensile and thermal properties PLA incorporated with PEG as plasticizer (PLA/PEG). PLA/PEG and FCHW reinforced PLA/PEG nanocomposites were prepared using solution mixing technique. Thermogravimetric analysis (TGA) was used to determine the thermal properties while tensile properties were determined from the tensile test. The incorporation of PEG successfully increased the ductility and tensile strength of PLA at the expense of modulus. Based on the tensile properties, 5 phr PEG was chosen for further investigation on the effect of FCHW on PEG modified PLA. Incorporation of 1 phr FCHW PLA/PEG increased the tensile strength and Young’s modulus. However, the tensile strength decreased with further addition of FCHW. The elongation at break of PLA/PEG decreased drastically with the incorporation of 1 phr FCHW and decreased gradually with further increase of FCHW. The thermal stability from TGA of FCHW reinforced PLA/PEG nanocomposites at 5 phr FCHW content was observed to be significantly higher compared to PLA/PEG, as indicated by T20 and Tmax.

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Zhang, Zhao, Guo Dong Fan, and Hai Yan Yang. "Study on Chain Extension and Modification of Poly(Lactic Acid) by Isophorone Diisocyanate /Polyethylene Glycol." Advanced Materials Research 476-478 (February 2012): 2067–70. http://dx.doi.org/10.4028/www.scientific.net/amr.476-478.2067.

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Poly(lactic acid)(PLA)was end-capped by isophorone diisocyanate(IPDI) to get PLA-IPDI under the condition of temperature of 176°C and pressure of 0.090 MPa for 13 mins, and then the PLA-IPDI was chain-extended with different molecular weights polyethylene glycol (PEG)-400, PEG-600, PEG-800, PEG-4000 and PEG-6000 to produce a series of block copolymer PLA-IPDI-PEGs. when n(–OH)/n(–NCO)=1.5:1, the molecular weight of PLA-IPDI is maximum. All the copolymer PLA-IPDI-PEGs were characterized by GPC, FTIR, DSC and contact angle testing. The results show that the polymeric degree of PLA-IPDI-PEG-800 is the best and its molecular weight is the biggest. Tg of PLA-IPDI-PEG-800 is the lowest and its hydrophilicity is better than the others modification PLA-IPD-PEGs and pure PLA.

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Mohd. Akhir, Nur Atiqah, Maizatulnisa Othman, Yose Fachmi Buys, Norhashimah Shaffiar, Dzun Noraini Jimat, and Sharifah Imihezri Syed Shaharuddin. "CHARACTERISATION AND PRODUCTION OF POLY (LACTIC ACID)/POLY(ETHYLENE GLYCOL) MICROFIBER VIA MELT DRAWN SPINNING PROCESS." IIUM Engineering Journal 22, no. 1 (2021): 201–12. http://dx.doi.org/10.31436/iiumej.v22i1.1364.

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In this study, melt blended compositions of pure PLA with additions of polyethylene glycol (PEG) up to 30 wt% were prepared. Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), and thermogravimetric analysis (TGA) were used to investigate the properties of PLA/PEG blends, such as structural, thermal, and morphological properties. The results showed that further increments of PEG cause the -OH group of PLA/PEG blends to show a broad peak, indicating that there is hydrogen bonding interaction between PEG and PLA chains. DSC result revealed that the addition of PEG decreases the glass transition temperature from 57 °C to 46 °C and crystallization temperature from 107 °C to 87 °C. Such trends suggest enhanced chain mobility of PLA chains. TGA thermograms showed that further additions of PEG into PLA resulted in a consistent shift to lower temperature and decrease in thermal stability. Optical microscopy (OM) and scanning electron microscopy (SEM) observations of the melt spun PLA/PEG microfibers revealed that the diameter of the microfibers averaged between 15 to 80 microns. ABSTRAK: Kajian ini menganalisa komposisi adunan lebur PLA asli bersama tambahan polietilena glikol (PEG) sebanyak 30%. Penjelmaan Fourier spektroskopi inframerah (FTIR), kalorimeter pengimbasan pembezaan (DSC) dan analisis termogravimetri (TGA) telah digunakan bagi mengkaji sifat-sifat adunan PLA/PEG, seperti struktur, terma dan sifat-sifat morfologi. Keputusan menunjukkan penambahan PEG seterusnya menyebabkan kumpulan -OH campuran PLA/PEG memberikan puncak yang lebar, ini menunjukkan ada interaksi ikatan hidrogen antara rantaian PEG dan PLA. Keputusan DSC menunjukkan penambahan PEG mengurangkan perubahan gelas dari 57 °C kepada 46 °C dan suhu kristalisasi dari 107 °C kepada 87 °C. Trend ini mencadangkan peningkatan pergerakan rangkaian pada rantaian PLA. Termogram TGA menunjukkan dengan penambahan berterusan PEG ke dalam PLA menghasilkan penurunan konsisten pada suhu dan pengurangan kestabilan haba. Pemerhatian mikroskop optik (OM) dan mikroskopi elektron penskanan (SEM) mikrofiber spun lebur PLA/PEG menunjukkan purata diameter mikrofiber ini antara 15 ke 80 mikron.

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Hendrick, Erin, and Margaret Frey. "Increasing Surface Hydrophilicity in Poly(Lactic Acid) Electrospun Fibers by Addition of Pla-b-Peg Co-Polymers." Journal of Engineered Fibers and Fabrics 9, no. 2 (2014): 155892501400900. http://dx.doi.org/10.1177/155892501400900219.

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Poly (lactic acid) – b – poly (ethylene glycol) (PLA-b-PEG) co-polymers with block lengths of 1000–750, 5000–1000, 1000–5000, and bulk PEG were added to PLA electrospinning dopes to create hydrophilic but non-water soluble nanofibers. PLA-b-PEG block lengths strongly affected the total amount of PEG that could be incorporated, as well as spinnability and fiber morphology. Solutions containing >1% w/w of the lowest molecular weight co-polymer PLA (1000) – b – PEG (750) formed an unspinnable, cloudy gel. Addition of the PLA (5000) – b – PEG (1000) to the base spinning solution influenced fiber diameters and spinnability in the same manner as simply increasing PLA concentration in the spinning dope. Addition of PLA (1000) – b – PEG (5000) resulted in decreased fiber diameters, and allowed for the highest overall co-polymer loading. In final fiber formulations, maximums of 0.9, 2.9 and 9.3 wt% PEG could be achieved using the PLA-b-PEG 1000–750, 5000–1000 and 1000–5000 respectively. PEG (MW = 3350 g/mol) homopolymer was added to the spinning dopes to prepare fibers with 1.0 and 5.0 wt% PEG. The resulting fibers had non-uniform morphology and more variable diameter size than occurred with the addition of PEG in block co-polymer form. Water absorbance by electrospun nonwoven fabrics increased by four times over the control PLA with the addition of 1.0 wt% PEG, and by eighteen times with the addition of 9.3 wt% PEG with the block co-polymers. At similar overall PEG loadings, the addition of PLA-b-PEG resulted in a two to four fold increase in water wicking over the addition of PEG homopolymer.

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Thong, Phan Quoc. "STRUCTURE AND PROPERTIES OF Fe3O4 NANOPARTICLES COATED BY PLA-PEG COPOLYMER WITH AND WITHOUT LOADING OF CURCUMIN." Vietnam Journal of Science and Technology 54, no. 1A (2018): 268. http://dx.doi.org/10.15625/2525-2518/54/1a/11837.

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Nanoparticles (NPs) of poly(lactide)-polyethylene glycol (PLA-PEG) with PLA:PEG (3:1, w/w) component ratio was prepared by ring opening polymerization of Lactide for preparation of Fe3O4@PLA-PEG and Fe3O4@PLA-PEG/Cur nanosystem. The Cur (curcumin) loaded Fe3O4 could be used as multi-functional nano drugs beneficiating both the image contrast enhancement and locally controlled heating. The size, shape, surface bonding of Fe3O4@PLA-PEG, Fe3O4@PLA-PEG/Cur nanosystems were determined by Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Thermal Gravity Analysis (TGA), Fourier Transform Infrared Spectroscopy (FT-IR); while magnetic characteristics by Vibrating Sample Magnetometer (VSM). The research suggests that Fe3O4@PLA-PEG and Fe3O4@PLA-PEG/Cur nanosystems exhibit properties of great potential for biomedical applications, both for diagnosis and treatment purposes.

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Thongpina, Chanchai, Chaiwat Tippuwanan, Kwanchai Buaksuntear, and Teerani Chuawittayawuta. "Mechanical and Thermal Properties of PLA Melt Blended with High Molecular Weight PEG Modified with Peroxide and Organo-Clay." Key Engineering Materials 751 (August 2017): 337–43. http://dx.doi.org/10.4028/www.scientific.net/kem.751.337.

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The thermal and mechanical properties of poly (lactic acid) blended with high molecular weight PEG, i.e. PEG1000 and PEG6000 were compared. The contents of PEG added were 10, 12.5 and 15 % by weight, with respect to PLA. The PLA/PEG blends were modified by addition of organic peroxide in order to induced crosslinking. Addition of organic modified montmorrillonite (Cloisite 30B, C30B) was also performed in order to modify mechanical performance of PLA/PEG blends. C30B was prepared via master batch in PLA. Morphology, crystallization, thermal stability and mechanical properties of the blends were investigated using SEM, DSC, TGA and universal testing macine, respectively. Morphology of cryogenic fracture surface showed smooth brittle surface. PEG1000 well plasticized PLA where as PEG6000 shows better thermal stability and mechanical properties. The presence of PEG induced PLA to perform cold crystallization. Tm in PLA was slightly changed whereas degree of crystallinity of PLA was improved by PEG but slightly decreased by peroxide. The thermal stability of PLA was enhanced with the addtion of PEG6000. The toughening of PLA was confirmed by the increment of elongation at break. The exfoliation of C30B was interfered by the crosslink PLA. Then tensile strength of PLA/PEG/C30B/Luperox101 was then suppressed. The optimum properties, in term of toughening and thermal stability, were found at PEG content of 10 % rather than 15% by weight, for both PEG1000 and PEG6000.

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Somphol, Wanasorn, Thipjak Na Lampang, Paweena Prapainainar, et al. "Effect of Polyethylene Glycol in Nanocellulose/PLA Composites." Key Engineering Materials 821 (September 2019): 89–95. http://dx.doi.org/10.4028/www.scientific.net/kem.821.89.

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Poly (lactic acid) or PLA was reinforced by nanocellulose and polyethylene glycol (PEG), which were introduced into PLA matrix from 0 to 3 wt.% to enhance compatibility and strength of the PLA. The nanocellulose was prepared by TEMPO-mediated oxidation from microcrystalline cellulose (MCC) powder and characterized by TEM, AFM, and XRD to reveal rod-like shaped nanocellulose with nanosized dimensions, high aspect ratio and high crystallinity. Films of nanocellulose/PEG/PLA nanocomposites were prepared by solvent casting method to evaluate the mechanical performance. It was found that the addition of PEG in nanocellulose-containing PLA films resulted in an increase in tensile modulus with only 1 wt% of PEG, where higher PEG concentrations negatively impacted the tensile strength. Furthermore, the tensile strength and modulus of nanocellulose/PEG/PLA nanocomposites were higher than the PLA/PEG composites due to the existence of nanocellulose chains. Visual traces of crazing were detailed to describe the deformation mechanism.

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Cavalli, Leticia Riboldi, Jalma Maria Klein, Ivana Greice Sandri та Rosmary Brandalise. "Este trabajo se centró en el desarrollo de envases activos biodegradables con mezclas de poli (ácido láctico) (PLA), poli (etileno-co-acetato de vinilo) (EVA), polietilenglicol (PEG) y quitosano (QUI). Se investigaron las características morfológicas térmicas y mecánicas de las mezclas, así como, al mismo tiempo, la actividad antifúngica del envase. Para evaluar la actividad antimicrobiana de las mezclas PLA/EVA/PEG/QUI, las muestras se insertaron entre rebanadas de pan sin conservantes para evaluar su vida útil. Al comparar entre PLA/EVA/PEG, mezclas de PLA/EVA/PEG/QUI y PLA puro fue posible evidenciar la miscibilidad parcial, la disminución de la temperatura de transición vítrea (Tg) al incorporar PEG en las mezclas, una disminución de la fuerza ﬂ exural del 71% y módulo de elasticidad del 80,4% a la mezcla PLA/ EVA/PEG/2.5QUI, así como un aumento del alargamiento a la rotura del 153% y del 392% a la tenacidad al impacto. Se observó un comportamiento similar a PLA/EVA/20PEG y PLA/EVA/PEG/5.0QUI. La película que contiene QUI entre las rebanadas de pan también influyó en la reducción de la actividad del agua y redujo aproximadamente un 35% en el recuento de mohos y levaduras en las rebanadas de pan. El quitosano en mezclas con PLA/EVA/PEG mostró potencial como agente antifúngico natural en envases de panadería." Research, Society and Development 10, № 9 (2021): e50010916964. http://dx.doi.org/10.33448/rsd-v10i9.16964.

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This work focused on the development of biodegradable active packaging with poly(lactic acid) (PLA), poly(ethylene-co-vinyl acetate) (EVA), polyethylene glycol (PEG) and chitosan (QUI) blends. It investigated thermal and mechanical morphological characteristics of the blends, as the same time, the antifungal activity of the packaging. To assess the antimicrobial activity of the PLA/EVA/PEG/QUI blends, the samples were inserted between slices of bread with no preservative to the evaluation of their shelf life. By comparing between PLA/EVA/PEG, PLA/EVA/PEG/QUI blends and neat PLA was possible to evidence the partial miscibility, decreased glass transition temperature (Tg) by incorporating PEG into the blends, a decrease in ﬂexural strength of 71% and elasticity modulus of 80.4% to PLA/EVA/PEG/2.5QUI blend, as well as an increase in elongation at break of 153% and 392% to impact toughness. A similar behavior was observed to PLA/EVA/20PEG and PLA/EVA/PEG/5.0QUI. The QUI-containing ﬁlm among the bread slices has also inﬂuenced the water activity reduction, and reduced about 35% in the count of molds and yeasts in the slices of bread. Chitosan in mixtures with PLA/EVA/PEG showed potential as a natural antifungal agent in bakery packaging.

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Shen, Peng, Kai Tu, Chang Yu Yang, Jian Li, and Ru Xu Du. "Preparation of Anti-Fouling Poly(Lactic Acid)(PLA) Hollow Fiber Membranes via Non-Solvent Induced Phase Separation." Advanced Materials Research 884-885 (January 2014): 112–16. http://dx.doi.org/10.4028/www.scientific.net/amr.884-885.112.

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Anti-fouling PLA hollow fibers were fabricated using synthesized PLA-PEG-PLA copolymer as an additive to improve the hydrophilicity. The tri-block copolymer was prepared by ring-opening polymerization and a hydrophilic copolymer processing good compatibility with PLA molecule was obtained and utilized to fabricate membrane with PLA by NIPS. Elemental analysis showed that PLA-PEG-PLA could stably exist in membranes and endow the membrane with persistent hydrophilic. Thus the contact angle decreased nearly 20o with 5% PLA-PEG-PLA content, resulting in higher water permeability and BSA rejection which indicated the anti-fouling property of PLA membrane was improved.

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Thanomsilp, C., and U. Phetthianchai. "Synthesis and Characterisation of PLA-CO-PEG Copolymers." Advanced Materials Research 506 (April 2012): 178–81. http://dx.doi.org/10.4028/www.scientific.net/amr.506.178.

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PLA-co-PEG copolymers synthesized through ring opening polymerization between a lactide monomer and PEG were solution-cast into films. The effect of the molecular weight of PEG and also the percentage of added PEG on the properties of the copolymers were studied. The molecular weight of PEG was 4000, 8000, and 20000 while the percentage of added PEG was varied from 10 to 50 mol%. The NMR spectrums confirmed that the ratio of PLA:PEG in the copolymers are close to the monomer feed of the respective monomers. DSC and TGA results showed that, compared to PLA, the PLA-co-PEG copolymers have slightly lower melting temperatures but similar thermal degradation temperatures. Both molecular weights and the percentage added of PEG influenced the properties of the films. As expected, the tensile strength and Youngs modulus of the PLA-co-PEG copolymer films were lower than that of neat PLA. Conversely, theelongation at break of the copolymer film was higher than that of the PLA when the molecular weight of PEG was 20000. This study suggests that high molecular weight PEG could be used to improve the flexibility of the polymer films.

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Chen, Chih Kuang, Wen Jen Lin, Guan You Chen, Yu Te Lin, Rong Siou Jhu, and Jia Horng Lin. "Synthesis of Poly(ethylene glycol)-Block-Poly(lactide) via Sequential Ring-Opening Polymerization Technique for Preparing Micellar Carriers." Applied Mechanics and Materials 749 (April 2015): 433–36. http://dx.doi.org/10.4028/www.scientific.net/amm.749.433.

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With the advancement of nanotechnology and material chemistry, micelles have emerged as one of the most attractive carriers for anticancer drug delivery. In this study, a newly developed polymerization technique termed as “sequential ring-opening polymerization (SROP)“ was used to synthesize poly (ethylene glycol)-block-polylactide-block-polylactide (PEG-PLA-PLAs). Utilizing the features of SROP, well-controlled chain length of two different PLA blocks by using PEG as initiator can be achieved. Two types of PEG-PLA-PLAs, PEG-PLA11-PLA11 and PEG-PLA18-PLA18, were successfully synthesized and characterized. Having amphiphilic properties, PEG-PLA-PLAs were used to form micelles through self-assembly. The effects of PLA length on the resultant micelles were thoroughly investigated.

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Hiemstra, Christine, Zhiyuan Zhong, Pieter J. Dijkstra, and Jan Feijen. "Stereocomplex Mediated Gelation of PEG-(PLA)2 and PEG-(PLA)8 Block Copolymers." Macromolecular Symposia 224, no. 1 (2005): 119–32. http://dx.doi.org/10.1002/masy.200550611.

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Du, Xu, Qin Wang, Chuan Dong Wang, and Yang Liu. "Synthesis and Self-Assembly Study of Biodegradable Amphiphilic Triblock Copolymers with PEG Block." Advanced Materials Research 998-999 (July 2014): 95–98. http://dx.doi.org/10.4028/www.scientific.net/amr.998-999.95.

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Three biodegradable amphiphilic triblock copolymers: polylactide-poly (ethylene glycol)-polylactide (PLA-PEG-PLA), poly (ε-caprolactone)-poly (ethylene glycol)-poly (ε-caprolactone) (PCL-PEG-PCL) and poly (lactide-glycolide)-poly (ethylene glycol)-poly (lactide-glycolide) (PLGA-PEG-PLGA) were synthesized. Their chemical structures were characterized. In aqueous solution, their self-assembly and degradation were studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Spherical micelles were formed in aqueous solution via self-assembly of the amphiphilic triblock copolymers. After degradation, the PLA-PEG-PLA and PCL-PEG-PCL micelles became smaller and the PLGA-PEG-PLGA micelles change to vesicles, which should mainly attribute to their different degradation speed.

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Bao, Wenting, Xianlong Zhang, Hong Wu, Rong Chen, and Shaoyun Guo. "Synergistic Effect of Ultrasound and Polyethylene Glycol on the Mechanism of the Controlled Drug Release from Polylactide Matrices." Polymers 11, no. 5 (2019): 880. http://dx.doi.org/10.3390/polym11050880.

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In this paper, the synergistic effect of ultrasound and polyethylene glycol (PEG) on the controlled release of a water soluble drug from polylactide (PLA) matrices was studied. When ultrasound was used following the hot melt extrusion (HME) of the PLA/model drug release system, the release of the model drug (Methylene Blue (MB)) from the PLA when immersed in phosphate buffered saline (PBS) was affected by the variation of the parameters of ultrasound. It was found that no more than 2% PLA dissolved during the in-vitro release study, and the release of the MB from the PLA was diffusion controlled and fit well with the Higuchi diffusion model. Polyethylene glycol (PEG), which has high hydrophilicity and rapid dissolution speed, was blended with the PLA during the melt extrusion to enhance the release of the MB. The analysis of the structure and properties of the in-vitro release tablets of PLA/PEG/MB indicated that the ultrasound could improve the dispersion of MB in the PLA/PEG blends and it could also change the structure and properties of the PLA/PEG blends. Due to the dissolution of the PEG in PBS, the release of the MB from the PLA/PEG drug carrier was a combination of diffusion and erosion controlled release. Thus a new mechanism combining of diffusion and erosion models and modified kinetics model was proposed to explain the release behavior.

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Chang, Jing, Zhe Yang, Junfeng Li, et al. "Preparation and In Vitro and In Vivo Antitumor Effects of VEGF Targeting Micelles." Technology in Cancer Research & Treatment 19 (January 1, 2020): 153303382095702. http://dx.doi.org/10.1177/1533033820957022.

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Background: Doxorubicin (DOX) has antitumor effects mediated by cell viability inhibition and by inducing cellular apoptosis. However, it has limited use in clinical applications due to various factors such as hydrophobicity, dose-dependent toxicity effects on normal tissues, short cycle retention time, and low targeting ability. This study aims at enhancing hydrophilicity of DOX to restrict its toxic effects to within or around the tumor sites and also to improve its targeting ability to enhance antitumor efficiency. Methods: Micelles composed of biodegradable poly (ethylene glycol)-poly (lactic acid) copolymers (PEG-PLA) were employed to deliver DOX via a self-assembly method and were coupled to VEGF antibodies. The morphology, size, and physical stability of PEG-PLA-DOX targeting VEGF micelles (VEGF-PEG-PLA-DOX micelles) were assessed. Then, the release ability of DOX from these micelles was monitored, and their drug loading capacity was calculated. MTT assay revealed the in vitro antitumor effect of VEGF-PEG-PLA-DOX micelles. Moreover, ROS release was measured to evaluate apoptotic effects of these nanoparticle micelles. In vivo therapeutic efficiencies of VEGF-PEG-PLA-DOX micelles on a lung cancer nude mouse model was evaluated. Results: DOX-loaded micelles were obtained with a drug loading capacity of 12.2% and were monodisperse with 220 nm average diameter and a controlled in vitro DOX release for extended periods. In addition, VEGF-PEG-PLA-DOX micelles displayed a larger cell viability inhibitory effect as measured via MTT assays and greater cell apoptosis induction through in vitro ROS levels compared with PEG-PLA-DOX micelles or free DOX. Furthermore, VEGF-PEG-PLA-DOX micelles could improve in vivo antitumor effects of DOX by reducing tumor volume and weight. Conclusions: VEGF-PEG-PLA-DOX micelles displayed a larger anti-tumor effect both in in vitro A549 cells and in an in vivo lung cancer nude mouse model compared with PEG-PLA-DOX micelles or free DOX, and hence they have potential clinical applications in human lung cancer therapy.

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Hu, Huan, Ang Xu, Dianfeng Zhang, Weiyi Zhou, Shaoxian Peng, and Xipo Zhao. "High-Toughness Poly(lactic Acid)/Starch Blends Prepared through Reactive Blending Plasticization and Compatibilization." Molecules 25, no. 24 (2020): 5951. http://dx.doi.org/10.3390/molecules25245951.

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In this study, poly(lactic acid) (PLA)/starch blends were prepared through reactive melt blending by using PLA and starch as raw materials and vegetable oil polyols, polyethylene glycol (PEG), and citric acid (CA) as additives. The effects of CA and PEG on the toughness of PLA/starch blends were analyzed using a mechanical performance test, scanning electron microscope analysis, differential scanning calorimetry, Fourier-transform infrared spectroscopy, X-ray diffraction, rheological analysis, and hydrophilicity test. Results showed that the elongation at break and impact strength of the PLA/premixed starch (PSt)/PEG/CA blend were 140.51% and 3.56 kJ·m−2, which were 13.4 and 1.8 times higher than those of pure PLA, respectively. The essence of the improvement in the toughness of the PLA/PSt/PEG/CA blend was the esterification reaction among CA, PEG, and starch. During the melt-blending process, the CA with abundant carboxyl groups reacted in the amorphous region of the starch. The shape and crystal form of the starch did not change, but the surface activity of the starch improved and consequently increased the adhesion between starch and PLA. As a plasticizer for PLA and starch, PEG effectively enhanced the mobility of the molecular chains. After PEG was dispersed, it participated in the esterification reaction of CA and starch at the interface and formed a branched/crosslinked copolymer that was embedded in the interface of PLA and starch. This copolymer further improved the compatibility of the PLA/starch blends. PEGs with small molecules and CA were used as compatibilizers to reduce the effect on PLA biodegradability. The esterification reaction on the starch surface improved the compatibilization and toughness of the PLA/starch blend materials and broadens their application prospects in the fields of medicine and high-fill packaging.

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Shen, Teng Fei, Man Geng Lu, and Li Yan Liang. "Microporous Bio-Membrane Materials Based on High Molecular Weight Polylactide and Low Molecular Weight Poly(ethylene glycol)." Advanced Materials Research 567 (September 2012): 123–26. http://dx.doi.org/10.4028/www.scientific.net/amr.567.123.

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In this work, microporous membrane biomaterials based on high weight molecular polylactide (PLA) and low molecular weight poly(ethylene glycol) (PEG) using rapid solvent evaporation method were prepared and investigated. The effect of PEG segments added on the thermal and degradation behaviors was studied. According to the results, produced PLA/PEG biomaterial has lower glass transition temperature (Tg)in comparison with neat PLA. It was also found that the degradation rates of the PLA/PEG biomaterials were significantly increased with adding of PEG, which explained by increasing hydrophilic groups. For better porous fixation, CL-blocked polyisocyanate (CL-bp), which was synthesized from reaction of isophorone diisocyanate (IPDI) with dimethylol propionic acid (DMPA) and Trimethylolpropane (TMP) followed by addition of caprolactam (CL), were introduced. The microporous forms were observed by the scanning electron microscope (SEM), which showed the mean diameters of prepared PLA/PEG microporous were around 10μm.

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Nguyen, Dac Tu, Phuong Thu Ha, Thi Van Khanh Bui, et al. "Evaluation of cytotoxicity and MRI contrast enhancement ability of Fe3O4@PLA-PEG iron oxide nanoparticles in vitro model." Ministry of Science and Technology, Vietnam 63, no. 8 (2021): 30–34. http://dx.doi.org/10.31276/vjst.63(8).30-34.

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SPIONs are composed of Fe3O4 or gamma Fe2O3 cores and a biocompatible shell from Dextran, PLA, PEG, Chitosan, or PVA. SPIONs have many important applications in medicine and biology such as cell sorting, drug carrier, magnetic hyperthermia, and magnetic resonance imaging (MRI). This study aims to check the ability of copolymer PLA-PEG coated Fe3O4 ferromagnetic nanosystems (Fe3O4@PLA-PEG) produced for MRI application. The results showed that these nanoparticles had non-toxicity on BT-474 and Sarcoma 180 cell lines. Evaluation on T2 imaging mode revealed that Fe3O4@PLA-PEG nanoparticles were capable of enhancing the MRI image contrast in different conditions, including water, cell lysates solution, and even inside the cells. The report demonstrates that Fe3O4@PLA-PEG nanoparticles have a high potential application in MRI for clinical diagnosis.

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Nasongkla, Norased, Patoomratana Tuchinda, Bamroong Munyoo, and Komgrit Eawsakul. "Preparation and Characterization of MUC-30-Loaded Polymeric Micelles against MCF-7 Cell Lines Using Molecular Docking Methods and In Vitro Study." Evidence-Based Complementary and Alternative Medicine 2021 (May 28, 2021): 1–9. http://dx.doi.org/10.1155/2021/5597681.

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MUC-30 is a hydrophobic compound which is active against the MCF-7 cancer cell line. In this study, MUC-30 was loaded in polymeric micelles to improve the water solubility and release rate. For prolonged MUC-30 release, MUC-30 was encapsulated in polymeric micelles using PEG-b-PLA and PEG-b-PCL as materials. Micelles prepared with 1 : 9 w per w ratios by film hydration achieved the highest entrapment efficiency (EE%). The EE% of MUC-30-loaded PEG-b-PCL micelles was approximately 30% greater than that of PEG-b-PLA micelles, due to the different H-bond formations between MUC-30 and the polymer membrane (PCL, 4; PLA, 3). The cytotoxic activity of MUC-30 against EGFR theoretically presented 399.31 nM (IC50 = 282.26 ng/mL) by molecular docking. In vitro cytotoxic activity of MUC-30 was confirmed by MTT assay. MUC-30 (IC50 = 11 ± 0.39 ng/mL) showed three-fold higher activity over MUC-30-loaded PEG-b-PLA micelles (IC50 = 37 ± 1.18 ng/mL) and two-fold higher over PEG-b-PCL micelles (IC50 = 75 ± 3.97 ng/mL). This was due to the higher release rate of MUC-30 from PEG-b-PLA micelles compared to PEG-b-PCL micelles. Therefore, MUC-30-loaded PEG-b-PLA micelles could be a promising candidate for breast cancer chemotherapy.

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He, Yihong, Cong Wu, Jiayu Duan, Junming Miao, Hongyu Ren, and Jiagang Liu. "Anti-Glioma Effect with Targeting Therapy Using Folate Modified Nano-Micelles Delivery Curcumin." Journal of Biomedical Nanotechnology 16, no. 1 (2020): 1–13. http://dx.doi.org/10.1166/jbn.2020.2878.

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Targeted drug delivery systems have currently demonstrated considerable potential clinical benefits in cancer treatment. Curcumin has become a candidate anti-tumor drug for the therapy of glioblastoma multiforme (GBM) by increasing cell apoptosis and suppressing cell proliferation. In current research, we explored a novel targeted drug delivery system with a self-assembly measure by curcumin, MPEG-PLA and Fa-PEG-PLA. Compared with free curcumin and Cur/MPEG-PLA, Cur/Fa-PEG-PLA can remarkably suppress the growth of GL261 cells and promote apoptotic rate. Moreover, after the procession of tumor-bearing mice with curcumin/Fa-PEG-PLA complex, tumor growth in subcutaneous and intracranial tumor models were repressed via suppressing angiogenesis and facilitating apoptosis in vivo. The Curcumin/Fa-PEG-PLA nanoparticle may be a novel drug for the therapy of GBM.

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Kumar, Manish, Daniel Unruh, Ralf Sindelar, and Franz Renz. "Preparation of Magnetic Polylactic Acid Fiber Mats by Electrospinning." Nano Hybrids and Composites 14 (March 2017): 39–47. http://dx.doi.org/10.4028/www.scientific.net/nhc.14.39.

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Poly(lactic acid) (PLA) is blended with Poly(ethylene glycol) (PEG) and magnetic nanoparticles (MNPs). A series of mixtures are converted to fibers via electrospinning at room temperature. The fiber diameter of PLA decreases on blending with PEG from 6 down to 3 micrometers and with PEG + MNPs down ca. 1 micrometer. The thermogravimetric study confirms the effect of blending, enhancing the stability on adding PEG to PLA. The magnetic properties of polymer fibers containing different concentrations of MNPs are studied by vibrating sample magnetometer. The fiber blends shows proportionally reduced saturation magnetization compared to pure magnetic nanoparticles. The MNPs –incorporated PLA-PEG nanocomposite mat show magnetization and therefore promise the possibility for temperature effects, such as hyperthermia treatment.

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Nashchekina, Yuliya, Pavel Nikonov, Alexey Nashchekin, and Natalya Mikhailova. "Functional Polylactide Blend Films for Controlling Mesenchymal Stem Cell Behaviour." Polymers 12, no. 9 (2020): 1969. http://dx.doi.org/10.3390/polym12091969.

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Polymer blending is a suitable physical modification method to create novel properties of different polymers. Blending polylactic acid (PLA) and polyethylene glycol (PEG) produces materials with a wide range of properties. This study was the first to investigate the effect of different isomeric forms of PLA and PEG with terminal amino groups to obtain biocompatible films for human mesenchymal stem cell cultivation. It has been shown by scanning electron microscopy that the surface topology changes to the greatest extent when using films obtained on the basis of poly(d,l-lactide) and PEG with high molecular weights (15,000 g/mol). In order to obtain thin films and rapid evaporation of the solvent, PEG is mixed with PLA and does not form a separate phase and is not further washed out during the incubation in water. The presence of PEG with terminal hydroxyl and amino groups in blend films after incubation in water was proven using Fourier transform infrared (FTIR) spectroscopy. Results of fluorescence microscopy demonstrated that blend films formed on PLA and polyethylene glycol diamine (PEG-NH2) are more suitable for cell spreading and focal contact formation compared to cells cultured on the surface of pure PLA films or films made from PLA and PEG.

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Ke, Weichang, Xiang Li, Mengyu Miao, Bing Liu, Xiaoyu Zhang, and Tong Liu. "Fabrication and Properties of Electrospun and Electrosprayed Polyethylene Glycol/Polylactic Acid (PEG/PLA) Films." Coatings 11, no. 7 (2021): 790. http://dx.doi.org/10.3390/coatings11070790.

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Polylactic acid (PLA) film is an alternative filter material for heat-not-burn (HNB) tobacco, but its controllability in cooling performance is limited. In this work, polyethylene glycol (PEG) was introduced to form a polyethylene glycol/polylactic acid (PEG/PLA) film by electrospinning or electrospraying techniques to enhance the cooling performance, due to its lower glass transition and melting temperatures. The PEG/PLA films with typical electrospun or electrosprayed morphologies were successfully fabricated. One typical endothermic peak at approximately 65 °C was clearly observed for the melting PEG phase in the heating process, and the re-crystallization temperature represented by an exothermic peak was effectively lowered to 90–110 °C during the cooling process, indicating that the cooling performance is greatly enhanced by the introduction of the PEG phase. Additionally, the wetting properties and adsorption properties were also intensively studied by characterizing the contact angles, and the as-prepared PEG/PLA films all showed good affinity to water, 1,2-propandiol and triglyceride. Furthermore, the PEG/PLA film with a PLA content of 35 wt.% revealed the largest elasticity modulus of 378.3 ± 68.5 MPa and tensile strength of 10.5 ± 1.1 MPa. The results achieved in this study can guide the development of other filter materials for HNB tobacco application.

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Chieng, Buong Woei, Ibrahim Nor Azowa, Wan Yunus Wan Md Zin, and Mohd Zobir Hussein. "Effects of Graphene Nanopletelets on Poly(Lactic Acid)/Poly(Ethylene Glycol) Polymer Nanocomposites." Advanced Materials Research 1024 (August 2014): 136–39. http://dx.doi.org/10.4028/www.scientific.net/amr.1024.136.

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Graphene nanoplatelets (xGnP) were investigated as a novel nanoreinforcement filler in poly (lactic acid)(PLA)/poly (ethylene glycol)(PEG) blends by melt blending method. The prepared nanocomposites exhibited a significant improvement in tensile properties at a low xGnP loading. The tensile properties demonstrated the addition of 0.3wt% of xGnP led to an increase of up to 32.7%, 69.5% and 21.9% in tensile strength, tensile modulus and elongation at break of the nanocomposites respectively, compared to PLA/PEG blend. The nanocomposites also shows enhanced thermal stability compared with PLA/PEG blend in thermogravimetry analysis (TGA). Scanning electron microscopy (SEM) image of PLA/PEG/0.3wt% xGnP displays good uniformity and more homogenous morphology.

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Wang, Jian Hua, Shuen Liang, Chun Rong Tian, Xiu Li Zhao, and Xiao Yan Lin. "Study on Degradable Polyurethane Foams with Mixed PEG/PCL and PLA/PCL Soft Segments." Advanced Materials Research 518-523 (May 2012): 821–27. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.821.

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Through inclusion of different polymer chains with different properties into polyurethane matrix, such as poly(ethylene glycol) (PEG), poly(ε-caprolactone) (PCL), poly(lactic acid) (PLA), or poly(tetramethylene oxide) (PTMG), degradable polyurethane foams (PUFs) with different molecular structure were prepared. Influences of molecular structure on PUF materials’ performance were studied systematically. When PEG, PCL, PLA, and PTMG serve as soft segment, PUFs’ storage modulus and glass transition temperature (Tg) of PUFs decrease with following order: PLA>PCL>PEG>PTMG (flexibility of PUFs varies oppositely). And degradability decreases according to following order: PEG>PLA>PCL>PTMG. With increasing content of PEG or PLA chains in PU matrix, mechanical performance of PUFs decrease gradually, but remains on the same order with conventional non-degradable PUFs. Through control on the contents of different kinds of polymer chains in soft segments of PUFs, fairly good degradability can be achieved, at whilst their basic mechanical performance is well guaranteed.

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Kruse, Magnus, Marc Greuel, Franziska Kreimendahl, et al. "Electro-spun PLA-PEG-yarns for tissue engineering applications." Biomedical Engineering / Biomedizinische Technik 63, no. 3 (2018): 231–43. http://dx.doi.org/10.1515/bmt-2017-0232.

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Abstract Electro-spinning is widely used in tissue-engineered applications mostly in form of non-woven structures. The development of e-spun yarn opens the door for textile fabrics which combine the micro to nanoscale dimension of electro-spun filaments with three-dimensional (3D) drapable textile fabrics. Therefore, the aim of the study was the implementation of a process for electro-spun yarns. Polylactic acid (PLA) and polyethylene glycol (PEG) were spun from chloroform solutions with varying PLA/PEG ratios (100:0, 90:10, 75:25 and 50:50). The yarn samples produced were analyzed regarding their morphology, tensile strength, water uptake and cytocompatibility. It was found that the yarn diameter decreased when the funnel collector rotation was increasd, however, the fiber diameter was not influenced. The tensile strength was also found to be dependent on the PEG content. While samples composed of 100% PLA showed a tensile strength of 2.5±0.7 cN/tex, the tensile strength increased with a decreasing PLA content (PLA 75%/PEG 25%) to 6.2±0.5 cN/tex. The variation of the PEG content also influenced the viscosity of the spinning solutions. The investigation of the cytocompatibility with endothelial cells was conducted for PLA/PEG 90:10 and 75:25 and indicated that the samples are cytocompatible.

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Drumond, Walker S., Shu Hui Wang, and Cheila G. Mothé. "Síntese e caracterização do copolímero poli (ácido lático-b-glicol etilênico)." Polímeros 14, no. 2 (2004): 74–79. http://dx.doi.org/10.1590/s0104-14282004000200009.

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Duas séries de copolímeros triblocos, poli (ácido lático-b-etileno glicol) (PLA-PEO-PLA), foram sintetizados a partir do éster cíclico l,l-lactideo, usando octoato de estanho como iniciador e poli (etileno glicol) (PEG) (Mn = 4000 ou 600), di-hidróxi terminado, como co-iniciador. A ligação química entre os segmentos PEG e PLA foi confirmada pelas técnicas de espectroscopia no infravermelho (FTIR) e Ressonância Magnética Nuclear de Hidrogênio (RMN-¹H) e análise térmica. O grau de polimerização do bloco PLA, DP PLA, no copolímero foi estimado por RMN-¹H e mostrou variação em função da massa molar do PEG e do aumento da concentração relativa de l,l lactídeo na mistura reacional. O aspecto dos copolímeros sintetizados variou de acordo com o tamanho dos blocos hidrofílico e hidrofóbico presentes em sua estrutura. Testes de solubilidade mostraram comportamento anfifílico para o produto sintetizado. Os segmentos de PLA formaram uma fase cristalina enquanto a fase cristalina correspondente aos segmentos PEG não foi observada.

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Chitrattha, Sasiprapa, and Thawatchai Phaechamud. "Modifying Poly(L-Lactic Acid) Matrix Film Properties with High Loaded Poly(Ethylene Glycol)." Key Engineering Materials 545 (March 2013): 57–62. http://dx.doi.org/10.4028/www.scientific.net/kem.545.57.

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Poly(L-lactic acid) (PLA) is a biodegradable and bioabsorbable polymer which has many potential uses. However, PLA shows the poor toughness, slow degradation rate and relatively hydrophobic.Poly(ethylene glycol) (PEG) is widely used as a plasticizer and of great interest because it presents outstanding properties, e.g. solubility in water and also in some organic solvents, lack of toxicity and absence of antigenicity and immunogenicity, which are essential for biomedical applications. The aim of this study was to investigate the ability of high amount PEG 400 to improve the characteristics of PLA matrix film. PLA matrix films were prepared using a solvent casting method and their various properties were investigated. Mechanical properties were determined with texture analyzer. Contact angle and surface free energy were measured using the goniometer. From the mechanical properties evaluated (tensile strength (TS) and elongation at break (E)), all plasticized PLA films exhibited the softer behavior and the plasticized PLA films with150 % PEG 400 indicated the higher % elongation at break than pure PLA, significantly. The contact angle and surface free energy values indicated that PEG 400 could improve the wettability of solventsand also increase % water sorption and % weight loss with as dose dependent.Surprisingly, SEM photographs revealed more porous structure as the higher amount PEG 400 was incorporated in PLA film. This porous structure and density of developed plasticized PLA film could be modified with temperature change technique. Parameters affecting the 3-D porous plasticized PLA matrix were revealed in this study. The optimum condition for producing the continuous 3-D porous plasticized PLA matrix was obtained. This porous topography in PLA matrix film will be applied further as material in tissue engineering and drug delivery systems.

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Scsukova, Sona, Mlynarcikova A. Bujnakova, A. Kiss, and E. Rollerova. "Adverse eff ects of polymeric nanoparticle poly(ethylene glycol)- block-polylactide methyl ether (PEG-b-PLA) on steroid hormone secretion by porcine granulosa cells." Endocrine Regulations 51, no. 2 (2017): 96–104. http://dx.doi.org/10.1515/enr-2017-0009.

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AbstractObjectives. Development of nanoparticles (NPs) for biomedical applications, including medical imaging and drug delivery, is currently undergoing a dramatic expansion. Diverse effects of different type NPs relating to mammalian reproductive tissues have been demonstrated. Th e objective of this study was to explore the in vitro effects of polymeric nanoparticle poly(ethylene glycol)-blockpolylactide methyl ether (PEG-b-PLA NPs) on functional state and viability of ovarian granulosa cells (GCs), which play an important role in maintaining ovarian function and female fertility.Methods. The GCs isolated from porcine ovarian follicles were incubated with the different concentrations of PEG-b-PLA NPs (PEG average Mn=350 g/mol and PLA average Mn=1000 g/mol; 0.2-100 μg/ml) or poly(ethylene glycol) with an average molecular weight of 300 (PEG-300; 0.2- 40 mg/ml) in the presence or absence of stimulators, follicle-stimulating hormone (FSH; 1 μg/ml), androstenedione (100 nM), forskolin (10 μM) or 8Br-cAMP (100 μM), for different time periods (24, 48, 72 h). At the end of the incubation, progesterone and estradiol levels produced by GCs were measured in the culture media by radioimmunoassay. Th e viability of GCs was determined by the method using a colorimetric assay with MTT.Results. Treatment of GCs with PEG-b-PLA NPs induced a significant decrease in basal as well as FSH-stimulated progesterone secretion above the concentration of 20 and 4 μg/ml, respectively. Moreover, PEG-b-PLA NPs reduced forskolin-stimulated, but not cAMP-stimulated progesterone production by GCs. A dose-dependent inhibition of androstenedione-stimulated estradiol release by GCs was found by the action of PEG-b-PLA NPs. Incubation of GCs with PEG-300 significantly inhibited basal as well as FSH-stimulated progesterone secretion above the concentration of 40 mg/ml. PEG-b-PLA NPs and PEG-300 significantly reduced the viability of GCs at the highest tested concentrations (100 μg/ml and 40 mg/ml, respectively).Conclusions. The obtained results indicate that polymeric NPs PEG-b-PLA might induce alterations in steroid hormone production by ovarian GCs and thereby could modify reproductive functions.

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Li, Feng, Suming Li, Abdelsalm El Ghzaoui, Helene Nouailhas, and Renxi Zhuo. "Synthesis and Gelation Properties of PEG−PLA−PEG Triblock Copolymers Obtained by Coupling Monohydroxylated PEG−PLA with Adipoyl Chloride." Langmuir 23, no. 5 (2007): 2778–83. http://dx.doi.org/10.1021/la0629025.

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Niu, Mingjun, Hao Wang, Jing Li, et al. "Polyethylene glycol grafted with carboxylated graphene oxide as a novel interface modifier for polylactic acid/graphene nanocomposites." Royal Society Open Science 7, no. 7 (2020): 192154. http://dx.doi.org/10.1098/rsos.192154.

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Strength and toughness are both of great importance for the application of polylactic acid (PLA). Unfortunately, these two properties are often contradictory. In this work, an effective and practical strategy is proposed by using carboxylated graphene oxide (GC) grafted with polyethylene glycol (PEG), i.e. GC-g-PEG. The synthesis procedure of GC-g-PEG is firstly optimized. Then, a series of PLA nanocomposites were prepared by the melt blending method via masterbatch. In comparison to that achieved over pure PLA, these nanocomposites are of higher crystallinity, thermal stability and mechanical strength. This is mainly attributed to well-tailored interface and good dispersion. Especially, while retaining the tensile strength of the original PLA, the elongation at break increases by seven times by adding 0.3 wt% GC-g-PEG.

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Dvořáková, Monika, Eva Rollerová, Soňa Scsuková, Alžbeta Bujňáková Mlynarčíková, Lucia Laubertová, and Ingrid Žitňanová. "Effect of Neonatal Exposure to Poly(Ethylene Glycol)-block-Poly(Lactic Acid) Nanoparticles on Oxidative State in Infantile and Adult Female Rats." Oxidative Medicine and Cellular Longevity 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/7430435.

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Our goal was to evaluate the potential health risk of the polymeric NP, poly(ethylene glycol)-block-poly(lactic acid) (PEG-b-PLA), from the view of redox imbalance of the organism in two different life stages. Female Wistar rats were neonatally administered intraperitoneally with PEG-b-PLA NPs [20 mg/kg of b.w. (PEG20) or 40 (PEG40) mg/kg of b.w.] from postnatal day 4 (PND4) to PND7. We measured antioxidant capacity (TEAC), level of protein carbonyls and lipoperoxides in plasma, activities of catalase, glutathione peroxidase (GPx), and superoxide dismutase (SOD) in hemolysates of infantile (sacrificed on PND17) and adult (sacrificed after PND176) rats. Compared to controls, neonatal PEG40 exposure induced a significant TEAC reduction in the infantile rats. Protein carbonyls and lipoperoxide levels were not affected after any dose of PEG-b-PLA NP administration. In adult rats, PEG20 administration caused a significant decrease of protein carbonyl levels compared to controls. In infantile rats, both doses of PEG-b-PLA NP administration increased catalase, Gpx, and SOD activities compared to controls. Surprisingly, in adult rats, the activities of Gpx and SOD decreased significantly after administration of both doses of PEG-b-PLA NPs. Obtained data indicate a possible age-related association between the oxidative status and neonatal PEG-b-PLA NP administration in female rats.

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Dai, Jin Xu, Qiang Yang, and Bao Jian Liu. "Crystallization Behavior of PLA/PEG/Nucleating Agent Blends." Advanced Materials Research 807-809 (September 2013): 578–81. http://dx.doi.org/10.4028/www.scientific.net/amr.807-809.578.

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A series of PLA blends were prepared by solution co-precipitation of polylactide (PLA), polyethylene glycol (PEG) and different crystallization nucleating agents. The crystallization behavior of blends was investigated by differential scanning calorimeter (DSC) and X-ray diffraction (XRD). The results showed that the crystallization ability of PLA blends was accelerated by plasticizer PEG, but the crystal structure of the obtained PLA blends was imperfect; the crystal structure and crystallization rate of the PLA blends were improved with the addition of nucleating agent, moreover, the crystallinity was 34.1% and 36.5%, respectively.

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Yoon, Young Il, Ko Eun Park, Seung Jin Lee, and Won Ho Park. "Fabrication of Microfibrous and Nano-/Microfibrous Scaffolds: Melt and Hybrid Electrospinning and Surface Modification of Poly(L-lactic acid) with Plasticizer." BioMed Research International 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/309048.

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Biodegradable poly(L-lactic acid) (PLA) fibrous scaffolds were prepared by electrospinning from a PLA melt containing poly(ethylene glycol) (PEG) as a plasticizer to obtain thinner fibers. The effects of PEG on the melt electrospinning of PLA were examined in terms of the melt viscosity and fiber diameter. Among the parameters, the content of PEG had a more significant effect on the average fiber diameter and its distribution than those of the spinning temperature. Furthermore, nano-/microfibrous silk fibroin (SF)/PLA and PLA/PLA composite scaffolds were fabricated by hybrid electrospinning, which involved a combination of solution electrospinning and melt electrospinning. The SF/PLA (20/80) scaffolds consisted of a randomly oriented structure of PLA microfibers (average fiber diameter = 8.9 µm) and SF nanofibers (average fiber diameter = 820 nm). The PLA nano-/microfiber (20/80) scaffolds were found to have similar pore parameters to the PLA microfiber scaffolds. The PLA scaffolds were treated with plasma in the presence of either oxygen or ammonia gas to modify the surface of the fibers. This approach of controlling the surface properties and diameter of fibers could be useful in the design and tailoring of novel scaffolds for tissue engineering.

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Chen, Ai-Zheng, Zheng Zhao, Shi-Bin Wang, Yi Li, Chen Zhao, and Yuan-Gang Liu. "A continuous RESS process to prepare PLA–PEG–PLA microparticles." Journal of Supercritical Fluids 59 (November 2011): 92–97. http://dx.doi.org/10.1016/j.supflu.2011.08.012.

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Ahmad, Ahmad Fahad, Sidek Ab Aziz, Zulkifly Abbas, et al. "Chemically Reduced Graphene Oxide-Reinforced Poly(Lactic Acid)/Poly(Ethylene Glycol) Nanocomposites: Preparation, Characterization, and Applications in Electromagnetic Interference Shielding." Polymers 11, no. 4 (2019): 661. http://dx.doi.org/10.3390/polym11040661.

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In this study, a nanocomposite of reduced graphene oxide (RGO) nanofiller-reinforcement poly(lactic acid) (PLA)/poly(ethylene glycol) (PEG) matrix was prepared via the melt blending method. The flexibility of PLA was improved by blending the polymer with a PEG plasticizer as a second polymer. To enhance the electromagnetic interference shielding properties of the nanocomposite, different RGO wt % were combined with the PLA/PEG blend. Using Fourier-transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM) and X-ray diffraction, the structural, microstructure, and morphological properties of the polymer and the RGO/PLA/PEG nanocomposites were examined. These studies showed that the RGO addition did not considerably affect the crystallinity of the resulting nanomaterials. Thermal analysis (TGA) reveals that the addition of RGO highly improved the thermal stability of PLA/PEG nanocomposites. The dielectric properties and electromagnetic interference shielding effectiveness of the synthesized nanocomposites were calculated and showed a higher SE total value than the target value (20 dB). On the other hand, the results showed an increased power loss by increasing the frequency and conversely decreased with an increased percentage of filler.

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Huang, Yi-You, Tze-Wen Chung, and Tzeng-wen Tzeng. "Drug release from PLA/PEG microparticulates." International Journal of Pharmaceutics 156, no. 1 (1997): 9–15. http://dx.doi.org/10.1016/s0378-5173(97)00154-3.

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Zarinkolah, Zohreh, Hamed Bagheri, Saman Hosseinkhani, and Maryam Nikkhah. "INVESTIGATION ON THE MECHANICAL, THERMAL, BIO-DEGRADATION, AND BIO-COMPATIBILITY PROPERTIES OF POLY (LACTIC ACID) / POLY (ETHYLENE GLYCOL) BLEND." IIUM Engineering Journal 22, no. 1 (2021): 223–33. http://dx.doi.org/10.31436/iiumej.v22i1.1478.

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Absorbable sutures are widely used in surgery. In addition to acceptable mechanical properties, the surgical sutures should exhibit favorable degradability properties. In this research, the mechanical and thermal properties, hydrophilicity, biodegradability, pH changes, and drug release profile of polylactic acid (PLA) and polyethylene glycol (PEG) alloy were examined to fabricate absorbable sutures. The test results for the mechanical properties showed that the strength of the PLA/PEG alloy decreased with increasing PEG content, leading to an increase in elongation. The differential thermal analysis indicated that the resulting material was above its glass transition temperature (Tg) at ambient temperature and was thus flexible enough. According to the degradation test results, the alloys were degraded similar to the commercial sample. Furthermore, the pH measurements revealed that the degradation of the alloy had no significant effect on the pH of the environment. Bupivacaine hydrochloride was incorporated into a certain amount of PLA and PEG, and the drug release rate was then measured. The sample provided a suitable substrate for burst release. Moreover, the cytotoxicity test was carried out to evaluate the biocompatibility properties of the PLA/PEG alloy and it was found that this alloy is biocompatible and the biocompatibility of the material decreases with increasing drug loading. ABSTRAK: Sutur boleh serap telah digunakan dalam pembedahan secara meluas. Tambahan kepada sifat-sifat mekanikal ini, sutur pembedahan perlu memiliki ciri-ciri kebolehurain yang dikehendaki. Dalam kajian ini, sifat-sifat mekanikal dan terma, kehidrofilikan, kebolehuraian, perubahan pH, dan profil penguraian ubat asid polilaktik (PLA) dan aloi polietilena glikol (PEG) telah dikaji bagi mencipta sutur boleh serap. Hasil kajian mendapati sifat-sifat mekanikal menunjukkan kekuatan PLA/PEG aloi berkurangan dengan penambahan level PEG, menyebabkan bertambahnya pemanjangan. Analisis pembezaan terma menunjukkan hasil bahan adalah melepasi suhu perubahan gelas (Tg) pada suhu sekitar dan oleh itu sangat lentur. Berdasarkan hasil kajian degradasi, aloi ini telah digradasi seperti sampel komersial. Tambahan lagi, ukuran pH menunjukkan degradasi aloi ini tidak menunjukkan kesan langsung pada pH persekitaran. Bupivacaine hidroklorida dimasukkan ke dalam PLA dan PEG, dan kadar ubat dibebaskan kemudiannya diukur. Sampel substrat yang bersesuian disediakan bagi pelepas letus. Tambahan, ujian Kesitotoksikan telah dijalankan bagi menilai ciri-ciri keserasian-bio aloi PLA/PEG dan didapati aloi ini serasi-bio dan keserasian-bio bahan berkurangan dengan penambahan beban ubat.

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Muranaka, Makoto, Ken Hirota, and Tsutomu Ono. "PEG–PLA nanoparticles prepared by emulsion solvent diffusion using oil-soluble and water-soluble PEG–PLA." Materials Letters 64, no. 8 (2010): 969–71. http://dx.doi.org/10.1016/j.matlet.2010.01.076.

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Alakrach, Abdulkader M., Nik Noriman Zulkepli, Awad A. Al-Rashdi, Sam Sung Ting, Rosniza Hamzah, and Omar S. Dahham. "Tailoring Polylactic Acid Properties for Packaging Applications: Effects of Co‐Addition of Halloysite Nanotubes and Selected Plasticizers." Materials Science Forum 1002 (July 2020): 47–56. http://dx.doi.org/10.4028/www.scientific.net/msf.1002.47.

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Polylactic acid (PLA) has recently given a huge attention because of its mechanical properties and good physical like good biodegradability and processability, high tensile modulus and strength. In the current research, the researchers utilized sesame oil (SO) and low molecular weight polyethylene glycol (PEG) as hydrophobic and hydrophilic plasticizers, towards improvise the ductility and toughness of PLA. The researchers synthesized nanocomposites by solution casting of the neat PLA/HNTs and PLA blends with weight ratio of (0,10, 20 and 30 wt%) for PEG and (0, 5 and 10 wt%) for SO. The influence of both plasticizers on chemical, thermal and mechanical properties of the nanocomposites were investigated. Characterization of the systems was achieved by mechanical testing and thermogravimetric analysis (TGA), field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FTIR). The FTIR analyses confirmed the existing of hydrogen bonding between PLA and both PEG and SO. significant improvement was shown by the plasticized nanocomposites in elongation at break with the adding of PEG and SO, meanwhile, the plasticized films’ strength were decreased. For the thermal analyses, all the films exhibited lower thermal stability compared to PLA/HNTs film.

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Tarach, Iwona, Ewa Olewnik-Kruszkowska, Agnieszka Richert, Magdalena Gierszewska, and Anna Rudawska. "Influence of Tea Tree Essential Oil and Poly(ethylene glycol) on Antibacterial and Physicochemical Properties of Polylactide-Based Films." Materials 13, no. 21 (2020): 4953. http://dx.doi.org/10.3390/ma13214953.

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The aim of the study was to establish the influence of poly(ethylene glycol) (PEG) on the properties of potential biodegradable packaging materials with antibacterial properties, based on polylactide (PLA) and tea tree essential oil (TTO). The obtained polymeric films consisted of PLA, a natural biocide, and tea tree essential oil (5–20 wt. %) was prepared with or without an addition of 5 wt. % PEG. The PLA-based materials have been tested, taking into account their morphology, and their thermal, mechanical and antibacterial properties against Staphylococcus aureus and Escherichia coli. It was established that the introduction of a plasticizer into the PLA–TTO systems leads to an increase in tensile strength, resistance to deformation, as well an increased thermal stability, in comparison to films modified using only TTO. The incorporation of 5 wt. % PEG in the PLA solution containing 5 wt. % TTO allowed us to obtain a material exhibiting a satisfactory antibacterial effect on both groups of representative bacteria. The presented results indicated a beneficial effect of PEG on the antibacterial and functional properties of materials with the addition of TTO.

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Zhang, Teng, and Su Mei Zheng. "Effect of Different Molecular Weight of PEG on the Crystallization Behaviors of Binary Polymer Blends PLA/TPS." Materials Science Forum 1035 (June 22, 2021): 918–24. http://dx.doi.org/10.4028/www.scientific.net/msf.1035.918.

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Serial poly (lactic acid) (PLA) and thermoplastic starch (TPS) blends (with a fixed content of 20 wt.% TPS) were prepared by melt extrusion process. The effect of different molecular weight of PEG on the thermal and rheological properties of PLA/TPS blends was studied by the melt ﬂow rate (MFR) and DSC analysis. The results showed that the molecular weight of PEG inﬂuenced the miscibility and crystallization behavior of PLA/TPS blends. Blend added with PEG400 showed a single Tg, and blends with PEG600 provided remarkable improvement of rheological properties with an increase in flow rate to 49.02 g/10 min. 4% content of poly (ethylene glycol) (PEG) can positively contribute to improve crystallization rate of PLA by reducing the melting temperature and cold crystallization temperature.

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Hashim, Norazlina, Kamala Retenam, Santhoshini Somderam, and Kamal Yusoh. "Effect of Processing Method on Thermal Behavior in PLA/PEG Melt Blending." Advanced Materials Research 1134 (December 2015): 185–90. http://dx.doi.org/10.4028/www.scientific.net/amr.1134.185.

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The dispersion of PEG acts as plasticizer in PLA blends were investigated using thermal analysis. The comparisons were made between two melt processing method, twin screw extruder and two-roll mills to study how it will affect theTg,TcandTmof blends in DSC analysis. The TGA behavior was also studied for two-roll mills processing method to confirm the effect of PEG loading in PLA on degradation and amount of residue left after analysis. In DSC analysis, it can be seen clearly, the PEG loading decreased the glass transition temperature in all blends compares to neat PLA. For twin screw extruder blending, the crystallization peak existed for some blend. It was difference for two-roll mills blends where the crystallization peak absent in all blends with PEG loading. The presence of PEG gave no significant variation on melting temperature peak for both processing method.

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Andima, Moses, Gabriella Costabile, Lorenz Isert, Albert Ndakala, Solomon Derese та Olivia Merkel. "Evaluation of β-Sitosterol Loaded PLGA and PEG-PLA Nanoparticles for Effective Treatment of Breast Cancer: Preparation, Physicochemical Characterization, and Antitumor Activity". Pharmaceutics 10, № 4 (2018): 232. http://dx.doi.org/10.3390/pharmaceutics10040232.

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β-Sitosterol (β-Sit) is a dietary phytosterol with demonstrated anticancer activity against a panel of cancers, but its poor solubility in water limits its bioavailability and therapeutic efficacy. In this study, poly(lactide-co-glycolic acid) (PLGA) and block copolymers of poly(ethylene glycol)-block-poly(lactic acid) (PEG-PLA) were used to encapsulate β-Sit into nanoparticles with the aim of enhancing its in vitro anticancer activity. β-Sitosterol-loaded PLGA and PEG-PLA nanoparticles (β-Sit-PLGA and β-Sit-PEG-PLA) were prepared by using a simple emulsion-solvent evaporation technique. The nanoparticles were characterized for size, particle size distribution, surface charge, and encapsulation efficiency. Their cellular uptake and antiproliferative activity was evaluated against MCF-7 and MDA-MB-231 human breast cancer cells using flow cytometry and MTT assays, respectively. β-Sit-PLGA and β-Sit-PEG-PLA nanoparticles were spherical in shape with average particle sizes of 215.0 ± 29.7 and 240.6 ± 23.3 nm, a zeta potential of −13.8 ± 1.61 and −23.5 ± 0.27 mV, respectively, and with narrow size distribution. The encapsulation efficiency of β-Sit was 62.89 ± 4.66 and 51.83 ± 19.72 % in PLGA and PEG-PLA nanoparticles, respectively. In vitro release in phosphate-buffered saline (PBS) and PBS/with 0.2% Tween 20 showed an initial burst release, followed by a sustained release for 408 h. β-Sit-PLGA nanoparticles were generally stable in a protein-rich medium, whereas β-Sit-PEG-PLA nanoparticles showed a tendency to aggregate. Flow cytometry analysis (FACS) indicated that β-Sit-PLGA nanoparticles were efficiently taken up by the cells in contrast to β-Sit-PEG-PLA nanoparticles. β-Sit-PLGA nanoparticles were therefore selected to evaluate antiproliferative activity. Cell viability was inhibited by up to 80% in a concentration range of 6.64–53.08 μg/mL compared to the untreated cells. Taken together, encapsulation of β-Sitosterol in PLGA nanoparticles is a promising strategy to enhance its anticancer activity against breast cancer cells.

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Chung, Y. Y. Huang, T. W. "Microencapsulation of gentamicin in biodegradable PLA and/or PLA/PEG copolymer." Journal of Microencapsulation 18, no. 4 (2001): 457–65. http://dx.doi.org/10.1080/02652040010019479.

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Zhang, Yan, Xiaohan Wu, Yaru Han, Fei Mo, Yourong Duan, and Suming Li. "Novel thymopentin release systems prepared from bioresorbable PLA–PEG–PLA hydrogels." International Journal of Pharmaceutics 386, no. 1-2 (2010): 15–22. http://dx.doi.org/10.1016/j.ijpharm.2009.10.045.

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Mainardes, Rubiana Mara, Najeh Maissar Khalil, and Maria Palmira Daflon Gremião. "Intranasal delivery of zidovudine by PLA and PLA–PEG blend nanoparticles." International Journal of Pharmaceutics 395, no. 1-2 (2010): 266–71. http://dx.doi.org/10.1016/j.ijpharm.2010.05.020.

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Huang, Ran, Boxin Zhou, Zhuping Nie, Weiwei Ding, Xilin Jiang, and Yihu Song. "A novel asymmetric amphiphilic porous film of (PLA)-(PLA-b-PEG)-(PEG) with controlled gradual pore size." Results in Materials 6 (June 2020): 100089. http://dx.doi.org/10.1016/j.rinma.2020.100089.

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Mohapatra, Aswini Kumar, Smita Mohanty, and Sanjay K. Nayak. "Properties and characterization of biodegradable poly(lactic acid) (PLA)/poly(ethylene glycol) (PEG) and PLA/PEG/organoclay." Journal of Thermoplastic Composite Materials 29, no. 4 (2014): 443–63. http://dx.doi.org/10.1177/0892705713518812.

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Journal articles on the topic 'PLA-PEG'

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