Formulation, optimization, and in-vivo evaluation of nanostructured lipid carriers loaded with Fexofenadine HCL for oral delivery

The aim of this study is to develop and optimize nanostructured lipid carriers (NLCs) for the delivery of fexofenadine hydrochloride (FEX). The goal is to prolong its action and improve its oral bioavailability. The solvent injection approach was used to successfully formulate Fexofenadine HCL loaded NLCs. The influence of the stearic acid/oleic acid ratio (X1) and sodium lauryl sulfate concentration (X2) on particle size (Y1) and entrapment efficiency (Y2) was investigated using a full factorial design (32), where a two factor was utilized in three levels. The optimized formula showed an average size of 127.5 ± 4.5 nm, a PDI of 0.205 ± 0.013, a zeta potential of −48.9 ± 2.5 mV, and an entrapment efficiency of 81.31 ± 2.4%. FT-IR, DSC, XRD, morphology, in-vitro release, stability analysis, and in-vivo study were performed on this formula. The results of the FT-IR experiments showed that there is no chemical interaction between FEX and the contents of NLCs. Due to the dispersion of the drug in the lipid mixture observed by DSC and confirmed by XRD, the crystallinity of FEX was reduced. SEM revealed that the NLCs were spherical particles. FEX-NLCs showed 82.11 ± 2.5% sustained release behavior over 48 h and significant stability in the refrigerator and at room temperature. When compared to the commercial Telfast® oral suspension, the optimized formula increased Fexofenadine HCL oral bioavailability by 2.57 times.