Enhanced intestinal absorption of asenapine maleate by fabricating solid lipid nanoparticles using TPGS: elucidation of transport mechanism, permeability across Caco-2 cell line and in vivo pharmacokinetic studies

The aim of the present investigation was to fabricate and evaluate solid lipid nanoparticles (SLNs) of asenapine maleate (AM) to improve its oral bioavailability (BA). AM-SLNs were prepared by high speed homogenization followed by ultrasonication technique. The resultant SLNs exhibited particle size, zeta potential and entrapment efficiency of 114.3 +/- 3.5nm, -12.9 +/- 3.8mV, and 84.10%+/- 2.90% respectively. In vitro release study of AM-SLNs showed 9.23%+/- 2.72% and 92.09%+/- 3.40% release of AM in pH 1.2 medium and phosphate buffer pH 6.8, respectively, indicating higher potential of lymphatic uptake. Cell viability study using Caco-2 cell line indicated non-toxicity of the carriers and drug. The uptake of AM-SLNs across Caco-2 cell line was time and energy dependent exhibiting clathrin-claveole mediated endocytosis transport. Cellular uptake of Coumarin loaded SLNs was effectively increased as compared to the dye solution. The pharmacokinetic results in rats showed 50.19-fold improvement in BA of AM after fabrication of SLNs. Collectively, all these findings demonstrated effectiveness of SLNs to improve therapeutic efficacy of AM in the treatment of schizophrenia.