A method for the simultaneous analysis of unconjugated and glycine-conjugated bile acids by capillary gas-liquid chromatography

A method for the simultaneous analysis of unconjugated and glycine-conjugated bile acids by means of capillary gas-liquid chromatography without need for prior deconjugation is described. The method involves: i) the use of an aluminum-clad fused-silica capillary column coated with a very thin film (0.1 micron) of a highly thermostable bonded and crosslinked methyl polysiloxane, and ii) the analysis of the bile acids as their methyl ester-dimethylethylsilyl ether derivatives. This method, used to separate the major free and glycine-conjugated bile acids from human gall bladder bile, should be applicable for the analysis of other biological fluids.