(509h) The Effect of Chitosan Surface Modification on PLGA Vascular Adhesion and Protein Adsorption for Improved Drug Delivery Systems

Vascular-targeted drug delivery systems require the successful localization and adhesion of drug carriers to diseased sites through the utilization of inflammatory biomarkers, such as overexpressed cell adhesion molecules. Poly (lactic-co-glycolic acid) (PLGA), a negatively charged copolymer, is the most appealing drug carrier material because of its tunable biodegradability, biocompatibility, and FDA approval. Unfortunately, the ability of PLGA to adhere to an inflamed endothelium is reduced in the presence of plasma proteins. The surface modification of PLGA by coating with chitosan (CS), a positively charged polysaccharide, is a potential approach to improve the adhesion of PLGA by altering the surface hydrophobicity and charge, which have an impact on plasma protein adsorption. In this study, we aimed to characterize the adhesion and plasma protein coronas of PLGA and CSPLGA particles conjugated with sialyl Lewis^a, targeting ligand, in physiological conditions. Using a parallel plate flow chamber assay, PLGA and CSPLGA particles were exposed to two mediums: red blood cells in viscous buffer and red blood cells in plasma. Our results indicate that CSPLGA particles significantly experience lower adhesion reduction in plasma compared to PLGA suggesting a difference in plasma protein adsorption. The level of reduction is dependent on donor plasma and the anticoagulant used. Ultimately, this contributes information to drug carrier design, specifically in terms of favorable surface hydrophobicity, charge, and protein coronas obtained.