Poly (Vinyl Alcohol) in Fabrication of PLA Micro- and Nanoparticles Using Emulsion and Solvent Evaporation Technique

Abstract

Poly (vinyl alcohol) (PVAL) was a common stabilizing agent used in formulate polymeric drug encapsulated micro-/nanoparticles. In preparing poly (lactic acid) (PLA) micro-/nanoparticles by emulsion and solvent evaporation (ESE) technique, the particle size and distribution have shown dependent on PVAL concentration. The focused of this project was to investigate the PVAL function in relation to significant changes in particle size. These studies were relatively important, as it was the basic studies of material usage in ESE fabricating process. The function of PVAL as, either surfactant that able to reduce interfacial tension or stabilizer to provide steric stability was further investigated by measuring the interfacial tension (IFT) of two liquids and zeta potential of the particles. As PVAL concentration increased, the reduction of IFT was only pronounced at the early stage of PVAL incorporation from 16.02 m N/m (absence of PVAL) to 2.0 m N/m (presence of 1 % PVAL), while zeta potential of particles was gradually decreased from-25 mV to-10.2 mV. As conclusion, the presence of PVAL could reduce the interfacial tension. However, to further stabilize the particle (e.g. reduce size and narrow size distribution) in the fabrication process, the steric stabilization provided by PVAL give more significant advantages.