Protein release from 25:75 microspheres

Lu, W., and Park,T. G. (1995), Protein release from poly(lactic-co-glycolic acid) microspheres Protein stability problems, PDA J. Pharm. Sci. Technol., 49,13-19. 

Zaky A, Elbakry A, Ehmer A, Breuning M, Goepferich A. (2010) The mechanism of protein release from triglyceride microspheres. Journal of Controlled Release 147 202-210. 

Yujie X., Pedro F.R., and Daniel W.P. Controlled protein release from monodisperse biodegradable double-wall microspheres of controllable shell thickness. J. Control. Release 172(3) (2013) 707-714. 

The ABA type block copolymer, PLA-PEG-PLA, has been most extensively studied since late 80 s in regard to its synthesis (22-27), properties 28,29), and degradability 30-34). In the ABA system, PEG works as an intermolecular plasticizer in processing implant pastes, films, and scaffolds. Its hydrogels have also been studied mainly for their biomedical application 35,36). Vert et al. have recently reported the utilization of the hydrogels to the protein release 37). Microspheres have been prepared from the ABA block copolymers by W/0 or W/O/W emulsion technique 38-40), and utilized for... 

PROTEIN RELEASE FROM DEGRADING DEXTRAN MICROSPHERES... 

PEG/PBT copolymers are also very good matrix materials for the release of growth factors in tissue engineering. Proteins have been delivered from PEG/PBT microspheres with preservation of protein delivery of complete activity. In the case of protein delivery from PLGA and poly(ortho ester) microspheres, the protein activity was significantly reduced. " ... 

Polyphosphazenes are a relatively new class of biodegradable polymers. Their hydrolytic stability or instability is determined not by changes in the backbone structure but by changes in the side groups attached to an unconventional macromolecular backbone. Synthetic flexibility and versatile adaptability of polyphosphazenes make them unique for drug delivery applications. For example, Veronese et al.18 prepared polyphos-phazene microspheres with phenylalanine ethyl ester as a phosphorous substituent and loaded it with succinylsulphathiazole or naproxen. The kinetics of release from these matrices were very convenient in yielding local concentrations of the two drugs that are useful per se or when mixed with hydroxyapatite for better bone formation. Polyphosphazene matrices are also considered as potential vehicles for the delivery of proteins and vaccines.19... 

Bittner, B., Witt, C., Mader, K., and Kissel, T. (1999), Degradation and protein release properties of microspheres prepared from biodegradable poly(lactide-co-glycolide) and ABA triblock copolymers Influence of buffer media on polymer erosion and bovine serum albumin release, J. Controlled Release, 60, 297-309. 

Crotts, G. Park, T.G. Protein delivery from poly(lactic-co-glycolic acid) biodegradable microspheres release kinetics and stability issues. J. of Microencap. 1998,15 (6), 699-713. 

G Crotts, TG Park. Protein delivery from poly(lactic-coglycolic acid) biodegradable microspheres Release kinetics and stabihty issues. J Microencapsul 15 699-713, 1998. 

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