Central Composite Design for Formulation and Optimization of Rifampicin Loaded Polylactide-Co-Glycolide Nanoparticles

The aim of this study was to synthesize and optimize polylactide-co-glycolide (PLGA) nanoparticles loaded with rifampicin (RIF), with a given size and high loading rate, using the central composite design (CCD) method. CCD was used to investigate the influence of independent factors such as PLGA:RIF ratio, type of PLGA, type and concentration of surfactants, power and duration of homogenization, and type of organic solvent and its ratio to the aqueous phase on the dependent physicochemical characteristics of the nanoparticles. The optimized nanoparticles were investigated using scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Comparative evaluation of the drug release kinetics was carried out using different pH and different setups: flow cuvette (USP 4 apparatus) and Franz diffusion cuvette. In addition, the mucoadhesive properties and mycobacterial activity of PLGA-RIF NPs were studied.