EFFECT OF LYOPHILIZATION ON THE PHYSICOCHEMICAL AND PHYSICOTECHNICAL PROPERTIES OF ASPIRIN-LOADED LIPOSPHERES
Objectives: To formulate aspirin-loaded lipospheres and to study the effect of lyophilization on the physicochemical and physicotechnical properties.
Materials and methods: Lipospheres were formulated using lipid matrix (LM) made from goat fat (70 %) and PhospholiponÂ® 90H (30 %) by hot homogenization. The formulations were lyophilized and analysed for particle size and morphology, percent drug content (PDC), and in vitro drug release. The micromeritic properties of the formulations were also studied.
Results and discussion: The unlyophilized lipospheres had particle size range of 35.9 Â± 8.63 to 78.7 Â± 3.30 Î¼m, while the lyophilized formulations had particle size range of 16.6 Â± 2.92 to 45.5 Â± 2.72 Î¼m. PDC of lipospheres ranged from 63.4 to 92 %. In vitro drug release showed about 92.4 and 91.3 % drug release at 5 h for A1 and B1lipospheres formulated with PoloxamerÂ® 407 and SoluplusÂ® respectively and containing 1 % of aspirin respectively, while 95 and 93 % was released at 8 h. The results of micromeritic studies showed that the lipospheres exhibited poor flowability.
Conclusion: Lyophilized aspirin-loaded lipospheres showed good properties and could be used orally twice daily.
Key words: Aspirin, lipids, micromeritic, lyophilization, NSAIDs