Adsorption of brain proteins on the surface of poly(D,L-lactide-co-glycolide) (PLGA) microspheres

Poly(D,L-lactide-co-glycolide) (PLGA) microspheres have been studied for intracerebral delivery of anticancer agents. To explore the biocompatibility nature of the polymer in brain, we have investigated the adsorption of brain proteins an the surfaces of PLGA microspheres. Microspheres were made by the solvent evaporation method using an oil/water (o/w) system. The brain protein adsorption experiment was performed by using a sonication eluting method. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to examine the brain proteins adsorbed. Ethyl cellulose microspheres were used in the study as a reference. The amount of brain proteins adsorbed on PLGA microspheres was also determined using a radiolabeling technique. The extent of brain proteins adsorbed on the PLGA microspheres was found to be lower than that adsorbed on the ethyl cellulose microspheres. The adsorption of brain proteins on PLGA microspheres, however, was significant, as indicated quantitatively by the I-125 labeling studies. The adsorption of brain proteins on the surface of the PLGA microspheres may be important when considering the use of this polymer as a brain implant delivery system.