Formulation of ibuprofen-loaded microemulsion-based hydrogel for topical administration

Abstract

Background: Ibuprofen (IBU) is a nonsteroidal antiinflammatory drug used to relieve pain and inflammation. Topical formulations of IBU can reduce unwanted side effects and first-pass metabolism in the liver. To enhance its waterpoor solubility and permeability for topical administration, this study aimed to develop and characterise hydrogels containing IBU microemulsion. Materials and methods: Pseudo-ternary phase diagrams were constructed based on the
evaluation of IBU solubility and the ratio of different excipients in the microemulsion formula. IBU microemulsion and IBU microemulsion-loaded hydrogels were characterised in terms of particle size and drug content by the high-performance liquid chromatography method. Ex vivo drug release through pig ear skin was evaluated using Hanson Research equipment. Results: The 1% xanthan gum hydrogel formula containing 5% (w/w) IBU microemulsion included 12.5% capryol 90, 33.33% acrysol K140, 16.67% propylene glycol and water (up to 100%, w/w) had a particle size of 25.69±2.12 nm and a polydispersity index of 0.226±0.095. The permeated drug percentage through the pig ear skin of the 1% xanthan gum hydrogel formula containing 5% (w/w) IBU microemulsion was 45-fold greater than that containing IBU material. Conclusion: These results showed that IBU-loaded microemulsion-based hydrogel would be a promising drug delivery system for topical administration.