Studies on the state of phosphatidylcholine molecules before and after ultrasonic and gel-filtration treatments

Phosphatidylcholine vesicles, prepared by prolonged ultrasonic irradiation in solution at 2°C under nitrogen followed by chromatography at 4°C on a Sepharose 4B column, were analyzed by thin-layer chromatography. No detectable differences were found in the chemical state of phosphatidylcholine molecules before and after the treatment by ultrasonic irradiation and gel-filtration. Special emphasis is given to the differences between the procedures for the preparation of homogeneous phosphatidylcholine vesicles and the conventional ultrasonication method.