Separation of sulfated from non-sulfated serum bile acids without the use of Sephadex columns

Abstract

Methods currently in use for the quantitative measurement of sulfated serum bile acids usually lead to low recoveries. The present technique uses two internal standards and involves enzymatic hydrolysis followed by extraction of the non-sulfated fraction in ether at pH 4.6. The sulfated fraction is then solvolysed before gas-liquid chromatographic analysis of the individual bile acids of both fractions. Using 200 microliters of serum, recoveries of more than 81% of sulfated bile acids were achieved. This method is of particular significance in view of recent evidence showing that certain sulfated bile acids are cholestatic.