NANOSPONGE LOADED HYDROGEL OF CEPHALEXIN FOR TOPICAL DELIVERY

Cephalexin is a first generation cephalosporin antibiotic which is used for the treatment of skin and soft tissue infection, urinary tract infection and diabetic foot infection. Since cephalexin is not available as topical formulation, cephalexin was formulated into nanosponge loaded hydrogel as it can enhance skin permeation. Nanosponges of cephalexin were prepared using hydroxyl ethyl cellulose and poly vinyl alcohol by emulsion solvent evaporation method. The particle size and entrapment efficiency was found in the range of 200- 400 nm and 88.5%- 95.6% respectively. Based on the characterization, nanopsonges with high entrapment efficiency and least particle size (NS2) was selected for hydrogel formulation. Five different formulations of hydrogels were prepared by using carbopol 934 with varying concentration of penetration enhancer (propylene glycol) and various evaluation studies were carried out. The in vitro release studies revealed that the formulation with higher concentration of penetration enhancer (15% propylene glycol) showed greater drug release. From the kinetic study, the best linearity was found with first order and Higuchi’s equation. The permeation studies showed that the formulation having higher concentration of permeation enhancer showed good skin permeation. The histological investigation on porcine skin indicated a disruption of the stratum corneum, suggesting improved permeation of the drug.