STUDIES ON SOLID-PHASE EXTRACTION OF BILE -ACIDS FROM BIOLOGICAL MATRIX

To quantify bile acids in biological samples, a solid phase extraction method was examined. This method is known as simpler procedures with less contamination compared with solvent extraction methods. Rat bile, feces and urine were used as biological samples. Since Bond Elut C18 and C8 were proved to be more suitable than the other phases (CH and S AX) so far examined using standard bile acids, Bond Elut C18 was used for biological samples. Quantification of biological sample was carrie d out by gas chromatography after the extracted sample was derivatized to methyl ester by treatment with trimethylsilyldiazomethane then to trifluoroacetyl ester by trifluoroacetic anhydride. On the gas chromat ography, two columns (Rtx-50 and Rtx-200) were connected to the inject or with Y-tube for elimination of interference. Except for a few bile acids, high recovery with less biological contamination was obtained b y this solid phase extraction method.