Solubilization by Triton X-100 makes possible complete recovery of lipids from liposomes in enzymatic assay

We have developed an accurate and sensitive method for enzymatically determining phosphatidylcholine (PC) and cholesterol (CHOL) in liposomes. Solubilizing liposomes with a high concentration (80%) of Triton X-100 at 65 degrees C for 5 min led to the complete recovery of the lipids by current assay using commercial kits. The method had good linearity in a range of 0.004-0.4 mumol PC. Using this method, PC and CHOL were completely recovered from various liposomes. We conclude that PC and CHOL in liposomes can be determined accurately and sensitively by this method.