Solubility of phosphatidylcholine in chloroform. Formation of hydrogen bonding between phosphatidylcholine and...

The solubility of phosphatidylcholine (PC) was studied by the spectroscopic analysis and the measurement of the solubility. The qualitative analysis of infrared absorption spectra confirmed the existence of two types of hydrogen bondings between chloroform and PC, one between chloroform and the C=O group of PC and the other between chloroform and the phosphorylcholine group of PC. The quantitative analysis of the C-D stretching vibration bands of the chloroform-d solution of PC showed that the latter hydrogen bonding mainly contributes to the solubility and that PC dissolves in chloroform to form a complex consisting of a few or more molecules of chloroform and one molecule of PC. We discussed in this report about the molecular organization of PC in chloroform solution.