New and versatile method for the determination of faecal bile acids by thin-layer chromatography with direct scanning...

A sensitive, versatile and precise method for quantitative analysis of individual faecal bile acids in humans by thin-layer chromatography with direct scanning fluorimetry is described. The method enables convenient quantitative measurements of faecal bile acids in larger series of samples for routine applications in gastroenterology. The overall coefficient of variation (including stool preparation and extraction) for the five predominant bile acids of human stool specimens (cholic acid, chenodeoxycholic acid, deoxycholic acid, lithocholic acid and ursodeoxycholic acid) was 3.4-4.9%. Recoveries of free bile acids added to the faeces ranged from 91% to 106%. An excellent and linear correlation between this method and fused-silica column gas chromatography with temperature programming was established (r = 0.91-0.99). In clinical practice this thin-layer chromatographic method constitutes a reliable, simple and time-saving alternative to gas chromatography.