In vitro and In vivo Characterisation of Piroxicam-Loaded Dika Wax Lipospheres

Purpose: To formulate piroxicam-loaded lipospheres and evaluate their in vitro and in vivo properties. Method: Piroxicam-loaded lipospheres were prepared by hot homogenization technique using dika wax and Phospholipon (R) 90G (1: 1, 1: 2 and 2: 1) as the lipid matrix. Characterisation, based on particle size and morphology, pH, drug content and encapsulation efficiency, were carried out on the lipospheres. In vitro release was evaluated in simulated intestinal fluid (pH 7.5). Anti-inflammatory and ulcerogenic properties of the piroxicam-loaded lipospheres were studied using healthy, adult Wistar rats. Result: Photomicrographs revealed spherical particles in the range of 1.66 - 3.56 mu m. The results also indicated that lipospheres formulated with lipid matrix 1: 1 and containing 0.25 % piroxicam had the highest encapsulation efficiency of 84 %. In vitro release data showed that lipospheres formulated with lipid matrix having higher concentration of dika wax exhibited the fastest drug release of drug with maximum release time between 60 - 70 min. The lipospheres exhibited good anti-inflammatory properties with 58.6 % oedema inhibition at 5 h. Piroxicam-loaded liposheres had an ulcer index of zero while, the reference (plain piroxicam) had an ulcer index of 15.00 +/- 1.23 (p < 0.05). Conclusion: Piroxicam lipospheres formulated with a mixture of dika wax and phospholipid exhibited good in vitro and in vivo properties.