Separation and quantitation of alkylphosphocholines and analogues of different liposome formulations by HPTLC

High-performance thin-layer chromatographic (HPTLC) analysis of non UV-acti ve phospholipids in biological matrixes is a common method for separation, detection, and quantitation. Liposomes containing new alkylphosphocholines and analogues with enhanced cytostatic activity had been prepared. The lipo somal formulations were designed to enable the intravenous application of t he alkylphosphocholines and analogues and to reduce dose-limiting toxicitie s observed after oral administration. For quality control the liposomes wer e analyzed by HPTLC for content of 1,2-dipalmitoyl-sn-glycero-3-phosphoglyc erol (DPPG), cholesterol, alkylphosphocholines, and analogues and their rel ated compounds (main degradation products). Due to the differences in lipop hily of the compounds, different mobile phases were necessary to achieve se paration. Automated Multiple Development was used to reduce the number of p lates and to improve the selectivity and the capacity of the chromatographi c system to separate the described alkylphosphocholines and analogues from DPPG and 1,2-dipaimitoyl-sn-glycero-3-phosphocholine in one chromatographic system.