Formulation Optimization of Erythromycin Solid Lipid Nanocarrier Using Response Surface Methodology

In present work response surface methodology (RSM) using the miscellaneous design model was used to optimize formulations of erythromycin solid lipid nanocarriers (ERY-SLN). Two-factor three level factorial design was considered for optimization. There were three parameters, drug entrapment efficiency (EE), drug loading (DL) percentage, and mean particle size of ERY-SLN, considered for investigating the optimal formulation with respect to two independent variables, including lipid concentration (X (1)) and surfactant : cosurfactant ratio (X (2)). The result showed that the optimal ERY-SLN was composed of lipid concentration (X (1)) 15 mg/mL and surfactant : cosurfactant ratio (X (2)) 1 : 1 with %EE of 88.40 ± 2.09%, DL of 29.46 ± 0.69%, mean particle size of 153.21 ± 2.31 nm, polydispersity index (PDI) of 0.026 ± 0.008, and zeta potential value of −15.18 ± (−5.53) mV. DSC and TEM study showed that there was no chemical interaction between ERY and lipid (GMS) and the ERY-SLN particles are nonspherical, respectively. The drug release experiments exhibited a sustained release over during 24 h, up to 66.26 ± 2.83%. Accelerated stability studies showed that there was no significant change occurring in the responses after storage condition for a total period of 3 months.