(637b) Preparation of Monodispersed Chitosan-Coated Poly(lactic-co-glycolic acid) Particles Suitable for Targeted Drug Delivery Applications

In recent years, the number of people suffering from cancers of all types is increasing rapidly. While many studies have been conducted for the improvement of conventional therapeutic approaches, one of the major concerns with regard to conventional chemotherapy continues to be the adverse effects of chemotherapeutic drugs on normal cells. Surface functionalization of carriers with ligands with specificity towards particular cells is a promising route to reduce collateral damage. However, the challenge is to bestow reactive properties on surfaces of carriers such as PLGA under conditions that are not adverse to the material or the function and further, to produce surface modified carriers with a narrow size distribution as required for controlled drug delivery. To address this issue, we have investigated the use of chitosan as a surface modifying agent to facilitate binding of target molecules and ligands.

The objective of the present study was to prepare chitosan-coated PLGA microparticles with a narrow particle size distribution. Current techniques have limitations in terms of fabricating uniform size particles in a continuous manner. Moreover, batch-to-batch differences in the size of the particles produced make it difficult to scale up the process. In this work, we have employed electrohydrodynamic atomization together with emulsion-evaporation for the fabrication of PLGA particles concomitantly coated by chitosan to produce monodispersed particles via a semi-continuous process. The chitosan-coated particles were spherical and show smooth surfaces, as observed by scanning electron microscopy (SEM). The core-shell structure was confirmed using laser scanning confocal microscopy (LSCM). Chitosan solution concentration was optimized to get desirable surface charge determined by Zeta potential measurement. Surface protein adsorption and stability of the coated particles were measured for the optimization of surface charge density. Finally, folic acid was chosen as the target molecules and successfully conjugated to the surface of the coated particles.

Simplicity and flexibility of the developed technique will open a new road for the fabrication of monodispersed multi-layered microparticles for different goals.