Microdetermination of cholesterol and phospholipid in cerebrospinal fluid and serum by silicic acid column chromatography.

A method is presented for the determination of cholesterol and phospholipid, which requires 5 I . of human serum or 1-2 ml. of cerebrospinal fluids. With this method 5-100 zg. of cholesterol and phospholipid can be separated by a modified silicic acid column after elution of the mixture with 1 ml. of chloroform and 3 ml. of methanol. Recovery for 24.6 sg. of cholesterol and 30.5 g. of phospholipid was 98.4 and 96.7%, respectively. Standard deviations of ±1.73 and ±1.24 have been obtained for the reproducibility of cholesterol and phospholipid determinations after chromatography. The method has been applied for the estimation of the cholesterol/ phospholipid ratio and of lipid phosphorus in total phosphorus of human cerebrospinal fluids.