Desirability combined response surface methodology approach for optimization of prednisolone acetate loaded chitosan nanoparticles and in-vitro assessment

Abstract

The objective of the current study was to design and optimize prednisolone acetate-loaded chitosan nanoparticles (NPs) through design experts for ophthalmic drug delivery. Chitosan NPs were prepared by ionic gelation using sodium tripolyphosphate (TPP). The effects of variables, such as chitosan concentration, chitosan to TPP mass ratio (ch:TPP), and prednisolone concentration on particle size, zeta potential (ZP), and polydispersity index (PDI), were studied using a three-factor three-level central composite design (CCD), and optimum experimental conditions were determined using the desirability function combined response surface methodology (RSM). Quadratic and reduced quadratic polynomial models were generated to predict and evaluate the independent variables with respect to the dependent variables. The composition of the optimal formulation was determined to be a chitosan concentration of 0.26%, chitosan to TPP mass ratio of 6:1, and drug concentration with respect to chitosan mass of 8.11%. The optimized formulation showed a percentage entrapment efficiency (%EE) of 78.32%, mean particle size of 193.5, PDI of 0.219, ZP of 10.3 mV, and 86.15% cumulative drug release. The morphology of the NPs was found to be nearly spherical in shape by scanning electron microscopy (SEM). Differential scanning calorimetry (DSC) revealed successful loading of the drug in NPs, and FTIR confirmed polymer and drug compatibility.