Abstract Polylactide (PLA)‐poly(ethylene glycol) (PEG) copolymers were synthesized from polyethylene glycol and D , L ‐lactide using low toxic stannous octoate as catalyst at 180°C by bulk polymerization. The characterized GPC, IR, 13 C‐NMR. A full assignment NMR spectrum is presented. physical, drug release, biodegradable properties in vitro of PLA–PEG investigated. result indicates that the rates release biodegradation could be tailored adjusting polymer composition. This amorphous...

ABA block copolymers of polyethylene glycol and poly-DL-lactic acid were prepared by ring-opening polymerization DL-dilactide with α,ω-dihydroxy glycol, n, 1000 or 2000. The morphology the resulting copolymers, PEG : PLA ratios(mol/mol) 1:2, 1: 3 1:4, was characterized DSC ESR spectroscopy. rate water uptake biphasic, reflecting contribution two processes: rapid diffusion into initially miscible blocks; then a slower hydration possibly due to phase separation hydrolytic cleavage blocks....

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMiscibility of copolymer blendsK. J. Zhu, S. F. Chen, Tai Ho, Eli M. Pearce, and T. K. KweiCite this: Macromolecules 1990, 23, 1, 150–154Publication Date (Print):January 1990Publication History Published online1 May 2002Published inissue 1 January 1990https://pubs.acs.org/doi/10.1021/ma00203a026https://doi.org/10.1021/ma00203a026research-articleACS PublicationsRequest reuse permissionsArticle Views370Altmetric-Citations53LEARN ABOUT THESE...

Poly(D,L-lactide-co-1,3-trimethylene carbonate) (PLCA) has been synthesized by ring-opening polymerization of 1,3-trimethylene carbonate (CA) and D,L-lactide (LA) using stannous octoate as catalyst. The copolymers were characterized 1H nuclear magnetic resonance (NMR), 13C NMR differential scanning calorimetry. Water content static contact angle distilled water on the polymer surface used to evaluate hydrophobicity polymers. It was found that increased with increasing CA fractions in...

Dapsone is still widely used for a range of infectious and inflammatory diseases. A potential severe side-effect, known as dapsone-induced hypersensitivity syndrome (DHS), may occur. DHS characterized by fever, skin rashes, lymphadenopathy multiorgan dysfunction manifesting hepatitis, cholangitis, pneumonitis, colitis, thyroiditis myocarditis. However, DHS-associated complete atrioventricular block has not previously been reported. We describe here 45-year-old Chinese woman who developed...

Polyester blending of poly(epsilon-caprolactone) (PCL) with poly(D, L-lactide) (PLA) and their random copolymers (R(CL/LA)) was found to be a convenient approach regulate the degradation drug release behaviors polyesters. The blend composition compatibility both affected its behavior. A DSC study showed that PCL compatible 50:50 poly(CL-CO-D,L-LA) (R(50/50)) but incompatible 25:75 poly(CL-CO-LA) (R(25/75)) PLA homopolymer. hydrolysis experiments indicated same CL/LA segment proportion,...

Poly(ethylene glycol) (PEG) segments were introduced into a polyanhydride main chain by copolymerization of terminal-carboxylated poly(ethylene with diacidic monomers (sebacic acid and trimellitylimidoglycine). IR 1H NMR spectroscopy confirmed the copolymer structures. DSC analysis showed that these polyanhydrides have low Tg crystallinity. In vitro degradation tests indicated introducing PEG accelerated rate polymers duration could be manipulated from 3 days to weeks. The pH environment...

In this paper, ibuprofen was encapsulated into microspheres by oil-in-water (o/w) emulsion solvent evaporation method. Biodegradable polymers with certain compositions and characteristics such as polylactide (PLA), poly(ϵ-caprolactone) (PCL) their block copolymer were used to prepare the microspheres. The results indicate that, under same processing conditions, drug entrapment efficiency similar (∼80%) for prepared PLA P(LA-b-CL) (78.7/21.3 mole), but it only 25.4% PCL in vitro release rate...

A modified double emulsion technique was adopted to prepare bovine serum albumin (BSA) loaded poly (D,l-lactic-co-glycolic acid) (PLGA) microspheres. In the formulations, polysorbates (Tween) such as Tween20®, Tween40® or Tween80®, instead of frequently used (vinyl alcohol) (PVA), emulsifier. Microspheres with porous surface, large particle size, low microsphere yield (∼65.4%) and BSA entrapment efficiency (∼25.2%) were obtained when Tween80® aqueous solution alone outer phase. However,...

This study evaluates a novel handheld sensor technology coupled with pattern recognition to provide real-time screening of several soybean traits for breeders and farmers, namely protein fat quality. We developed predictive regression models that can quantify quality based on near-infrared (NIR) spectra acquired by instrument. system has been utilized measure crude protein, essential amino acids (lysine, threonine, methionine, tryptophan, cysteine) composition, total fat, the profile major...

A modified oil-in-oil (o/o) emulsion solvent evaporation technique was adopted to prepare 5-fluorouracil (5-Fu)-loaded poly (L-lactide) (PLLA) or its carbonate copolymer microspheres. The disperse phase a drug:polymer solution using mixture of N,N-dimethylformamide (DMF) and acetonitrile the continuous liquid paraffin containing 1-10% (w/v) Span 80(R). effects preparative parameters, such as composition inner oil phase, ratio, polymer concentration agitation rate, on 5-Fu entrapment...

The process parameters such as the compositions of inner and outer aqueous phase emulsification technique primary emulsion were optimized to decrease burst release BSA from biodegradable polymer microspheres in double method. It was found that diminished –14% achieved for produced by formulations, where no phosphate present water (non-buffered system). Primary made probe sonication rather than homogenization or mechanical stirring led with insignificant effect. Microspheres obtained using...

Poly(1,3-trimethylene carbonate-co-glycolide) (PGCA) has been synthesized by ring-opening polymerization of 1,3-trimethylene carbonate (CA) and glycolide (GA) with stannous octoate as catalyst. The copolymers were characterized 1H nuclear magnetic resonance (NMR), 13C NMR differential scanning calorimetry. Water content static contact angle distilled water on the polymer surface used to evaluate hydrophobicity copolymers. There was no apparent difference in hydrophobicities containing up 30...

AbstractA modified oil-in-oil (o/o) emulsion solvent evaporation technique was adopted to prepare 5-fluorouracil (5-Fu)-loaded poly (L-lactide) (PLLA) or its carbonate copolymer microspheres. The disperse phase a drug:polymer solution using mixture of N, N-dimethylformamide (DMF) and acetonitrile the continuous liquid paraffin containing 1–10% (w/v) Span 80®. effects preparative parameters, such as composition inner oil phase, ratio, polymer concentration agitation rate, on 5-Fu entrapment...