Formulation, Characterization and in-vitro Evaluation of Famciclovir Loaded Solid Lipid Nanoparticles for Improved Oral Absorption

Famciclovir loaded Solid Lipid Nanoparticles (SLNs) using triglycerides as solid lipids were successfully prepared using the double emulsion-solvent evaporation technique. Formulation parameters like amount and type of lipid and level of surfactants affected the nanoparticle characters. It was observed that nanoparticle characters like average particle size and distribution, drug content, entrapment efficiency and release pattern were dependent on these formulation variables. The optimized formulations depicted the desired characters of low particle size, in the range of 140-170 nm in case of Glyceryl monostearate (GMS) and glyceryl distearate (GDS) SLNs and 250-340 nm in case of glyceryl behenate (GB) SLNs and entrapment efficiencies in the range of 35-48%. In vitro drug release was extended upto 8 h and the release profile was explained by the Baker-Lonsdale model for spherical particles. Morphological examination by Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) displayed homogenous solid, spherical and non- porous particles. The formulations depicted good redispersibility after lyophilization and presence of residual solvents in the formulations within the prescribed limits suggested suitability of the preparation technique. Freeze- dried formulations were found to be stable in terms of particle size and drug loading even after 6 months of storage at refrigerated conditions.