Résumé
Objective To develop a method for the synthesis of poly [lactic-co-(glycolic acid)] (PLGA) wrinkled microparticles,and to investigate their immobilization on model protein,i.e.bovine serum albumin (BSA),so as to provide a scientific basis for the preparation of artificial antigen-presenting cells (aAPCs).PLGA wrinkled microparticles were prepared by double emulsion-solvent evaporation method combined with porogen NH4HCO3.The effects of PLGA relative molecular mass,porogen mass concentration and double emulsion stirring speed on the morphology of PLGA micro particles were investigated.The PLGA wrinkled particles were incubated with different concentrations of FITC-conjugated BSA (FITC-BSA).The levels of BGA loaded with PLGA wrinkled particles were detected by laser scanning confocal microscopy,flow cytometry and diquinoline formic acid.The effect of the loading process on the BSA structure was analyzed by circular dichroism spectrometer.Results The molecular weight of 5 000 was the optimized parameters for PLGA wrinkled microparticles preparation.The morphology of PLGA wrinkled particles could be maintained when the mass concentration of porogen NH4HCO3 was less than 10 g/L.When the mixing speed of multiple emulsion increased from 400 r/min to 3 600 r/min,the average particle size of PLGA wrinkled particles decreased from 35 μm to 9 μm,which meets the size requirement of artificial aAPCs.The fluorescence intensity of PLGA wrinkled particles was directly proportional to the concentration of BSA,and the BSA structure was not affected by the adsorption of BSA by the PLGA wrinkled particles.Conclusion The relative molecular mass of PLGA has an important influence on the morphology of the particles.PLGA with a relative molecular mass of 5 000 can be used to prepare particles with a wrinkled topology,which can load proteinaceous macromolecules and maintain protein activity.This result has potential applications in artificial aAPCs.