PLGA nano- and microparticles for the controlled release of florfenicol: Experimental and theoretical study

Abstract

In this study, PLGA particle systems were studied for the controlled release of florfenicol, a broad spectrum antibiotic used in veterinary treatments. The emulsion-solvent evaporation technique was used for particle preparation. To evaluate the particle size, entrapment efficiency, and drug release behavior, factors such as solvent type, emulsification time and methods, and drug to polymer ratio were investigated. The results showed that the use of ethyl acetate and 2.5 min of ultrasonication or 30 min of homogenization can lead to sub-micron and micron-sized particles, respectively. Sizes between 200–300 nm and 2–3 μm were obtained for ultrasonication and homogenization procedures, respectively. Entrapment efficiencies were around 20% for all systems and release profiles were size dependent. In addition, a mathematical model was implemented to simulate the florfenicol transport. The model predicts the florfenicol release and takes into account the particle size, polymer molecular weight, and autocatalytic polymer degradation. Simulation results are in good agreement with experimental results.