PLGA copolymers

PLLA, PLGA copolymers, and PGA have proven to be biocompatible materials and are FDA approved for several applications. However, one drawback to their use as scaffold materials for organ regeneration is the acidity caused by the release of lactic and glycolic acid, which at high concentrations becomes toxic to surrounding tissues. Initially, the amount of acid released... 

Figure 9.6 Effect of lactide-to-glycolide ratio on the in vitro release of etoposide from PLGA copolymer microparticles.

Plasmid DNA has also been incorporated into PLGA copolymer matrices using gas foaming (137). The incorporation efficiency of the DNA... 

Qiao M, Chen D, Ma X, Liu Y. Injectable biodegradable temperature-responsive PLGA PEG-PLGA copolymers Synthesis and effect of copolymer composition on the drug release from the copolymer-based hydrogels. Int J Pharm 2005 294 103 112. 

The stability of vaccines was enhanced in several ways against destabilizing solvents and polymers. By careful selection of the PLGA copolymer composition and molecular weight, an oil (mineral oil)-based cores of tetanus toxoid surrounded by outer polymer shells (PLGA) potentially protecting the bioactive material against water-mediated inactivation processes. However, adjuvants such as trehalose, threonyl muramyl dipeptide, " BSA, - and PEG 400 can also be used for this purpose. 

Shah, N.H. et al, 1993. A biodegradable injectable implant for delivering micro and macromolecules using poly(lactic-co-glycolic) acid (PLGA) copolymers. Journal of... 

Shah, N. H., Railkar, A. S., Chen, F. C., Tarantino, R., Kumar, S., Muijani, M., Palmer, D., Infeld, M. H. Malick, A. W. (1993) A biodegradable injectable implant for dehvering micro and macromolecules using poly (lactic-co-glycohc) acid (PLGA) copolymers. Journal of Controlled Release, 21, 139-47. 

A gel duration from a week to several months was realized by topological variation of the PEG/PLGA copolymer system. The PEG-g-PLGA showed one week of gel duration, whereas PLGA-g-PEG showed more than three months of gel duration, even though the composition of the two polymers was similar. 

The thermogelling PLGA is an amorphous polymer with a low glass transition temperature. Therefore, the PEG/PLGA copolymer systems of which... 

Preparation 8-2 A poly(lactic-co-glycolic acid) (PLGA) copolymer with lactic acid and glycolic acid in the weight ratio of 50 50 is dissolved in a mixture of dioxane and water to provide a 5% PLGA solution. Then, an effervescent mixture of sodium hydrogen carbonate and citric acid is added and uniformly mixed therein. 

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