Preparation of Melatonin-Loaded Zein Nanoparticles using Supercritical CO2 Antisolvent and in vitro Release Evaluation

Abstract

Abstract In this work, we reported preparation of melatonin-loaded zein nanoparticles using the technique of solution-enhanced dispersion by supercritical CO2 (SEDS) for prolonging the release of melatonin. The influence of pressure, temperature and the ratio of melatonin and zein on the morphology, the particle size and drug loading was investigated. The release profiles of the melatonin-loaded nanoparticles were evaluated. The sizes of the most particles were less than 100 nm at most conditions examined, and the morphology had three types: rod-like, globule, and filament. The maximum drug loading of 6.9% and encapsulation efficiencies of 80.2% were obtained, respectively, under different conditions. The release speed of the melatonin in the nanoparticles is lower than both the pure one and that in the physical mixture. It displayed a near zero-order release which implied that it could be applied as a potential controlled-release drug.