Fabrication of poly(d,l-lactide-co-glycolide) nanoparticles using a simple fluidic device with a tapered glass capillary and the effect of thermodynamic parameters

Abstract

Poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles were prepared by nanoprecipitation method using a simple fluidic device with pristine and tapered glass capillaries. An organic PLGA solution and an aqueous poly(vinyl alcohol) solution were introduced into the fluidic device as the discontinuous and continuous phases, respectively. Five kinds of water-miscible solvents including acetone, acetonitrile, dimethyl formamide, dimethyl sulfoxide, and tetrahydrofuran were chosen as solvents for PLGA. This study investigated the effect of thermodynamic parameters such as diffusion coefficients (Dsw, Dws), exchange ratio (R = Dsw/Dws), and solvent–polymer interaction parameter (χ) on the size variation of PLGA nanoparticles. It was found that the size of PLGA nanoparticles was inversely proportional to the exchange ratio and solvent–polymer interaction parameter. This variation in size might be attributed to the production of smaller local supersaturation region in the case of lower exchange ratio and solvent–polymer interaction parameter. In addition, the size of PLGA nanoparticles could be tuned by changing the polymer concentration and flow rates in the fluidic device. This thermodynamic approach provides a rational basis for the selection of solvent to control the nanoparticle size.