PREPARATION AND EVALUATION OF LOXOPROFEN SOLID LIPID NANOPARTICLES LOADED GEL.

Abstract

Loxoprofen (LX), a non-steroidal anti-inflammatory drug (NSAID) known for its effectiveness in managing pain and inflammation. Conventional plain gel formulations, often require frequent application due to their rapid drug release and short duration of action, which can compromise patient compliance and therapeutic efficacy. Therefore, this study aimed to develop and evaluate a transdermal gel formulation incorporating Loxoprofen-loaded solid lipid nanoparticles (LX-SLNs), with the goal of achieving sustained anti-inflammatory activity. LX-SLNs were prepared using probe ultrasonication with glyceryl monostearate (GMS) as the lipid and Poloxamer 407 as the surfactant. The prepared LX-SLNs were lyophilized and incorporated into Carbopol 934 based gels. The prepared gels were evaluated for pH, physical properties, drug content, spreadability, extudability, rheological behavior, in-vitro drug release and ex-vivo skin permeation and retention studies were performed using rabbit skin in Franz diffusion cells. In-vivo anti-inflammatory activity of LX-SLNs loaded gel was assessed in Sprague-Dawley rats using the egg albumin-induced paw edema model. At the end of the In-vivo anti-inflammatory study the paws were excised for histological evaluation. The preferred formula GF1 exhibited a pH within the acceptable range, uniform drug content, good spreadability, and pseudoplastic flow behavior. In-vitro release revealed sustained drug release over 12 hours. Ex-vivo permeation studies confirmed enhanced transdermal flux and skin retention compared to plain LX gel. In-vivo, the LX-SLNs gel demonstrated significantly higher inhibition of paw edema (p < 0.05), indicating superior anti-inflammatory efficacy. In conclusion, LX-SLNs gel offered a promising strategy for sustained delivery of LX with enhanced skin permeation and anti-inflammatory effects.