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AAPS PharmSciTech. 2001 December; 2(4): 86–92.
Published online 2015 February 19. doi:  10.1007/BF02830570
PMCID: PMC2784845

Effect of additives on the release of a model protein from PLGA microspheres


The purpose of this study was to investigate the effect of 2 additives, poly(ethylene glycol (PEG) 1000 and 1,2,3-tridecanoyl glycerol (tricaprin), on the physico-chemical characteristics and in vitro release of a model protein, bovine serum albumin (BSA), form poly(D,L-lactic-co-glycolic acid) (PLGA) microspheres. BSA-loaded microspheres were prepared by the double emulsion solvent evaporation method. Additives were incorporated into microspheres to modify the release of protein. The addition of PEG 1000 and tricaprin changed the surface characteristics of microspheres from smooth and nonporous to porous and dimpled, respectively. The in vitro release profiles showed that the additives significantly (P<0.05) increased the early-stage release of BSA from microspheres.

Keywords: microspheres, poly(D,L-lactic-co-glycolic acid), bovine serum albumin, poly(ethylene glycol), tricaprin, morphology, and in vitro release

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
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