Author(s): M. Parvathi1*,J. Raveendra Reddy1andD. SubbaRao2
The objective of this study wasto formulate and optimize PA loaded SLNs usingvarious solid lipids. The SLNs were prepared from phase behaviours of hot microemulsions-ultra probe sonication technique.The phase diagrams were prepared from lipid/Smix at 60oc using prosimsoftware. The analogy between design factors and experimental data was studied using response surface methodology(RSM). A statistical technique of RSM with Box-Behnken design wasframed to study and determine the influence of formulation independent factors including a solidlipid (x1), surfactant/co-surfactant ratio (x2), sonication time (x3). The dependent factors were particle size, entrapment efficiency(%EE). Tristearin showed better stability and low particle size hence selected for the study. The prepared nanoparticles were in a spherical shape and average particle size of 24.69 nm andthe polydispersity index, zeta potential and %EE range of -0.274, -28.47mV & 89.82% respectively. In Vitro diffusion studies showed a burst release at the initial stage followed by prolonged release of PA from SLNs up to 15hrs and drug diffusion found to be 94.85%. The release kinetics of the optimized formulation was best fitted the zero order model (R2-0.9938).These results concluded that the prednisolone acetate –loaded SLNs could potentially be exploited as a delivery system with improved drug entrapment efficiency, low mean particle size and controlled drug release.