Semiautomated spectrophotometry of total phospholipids in plasma

A one-stage semiautomated method for estimating total phospholipids in plasma is reported. The phospholipids are extracted into aqueous ethanol, combined with a Lewis acid, and the change in pH is monitored colorimetrically. The method, compared with the acid digestion method of Gomori [J. Lab. Clin. Med. 27, 955 (1942)], gives results that are about 0.25 mmol/liter lower, but seems to be a suitable and less hazardous alternative.