Determination of urinary cholic and chenodeoxycholic acid conjugates with radioimmunoassay

Radioimmunoassays were developed for the determination of urinary unsulphated and total cholic and chenodeoxycholic acid conjugates. For the determination of unsulphated bile acid conjugates the urine was assayed directly after adjustment of pH to 7.4. The total conjugates were determined after extraction of the bile acids on an XAD-2 column, solvolysis of the sulphated bile acids and purification on a second XAD-2 column. Comparison of the results obtained using radioimmunoassay with those obtained using gas chromatography on twenty-two urine samples from patients with different types of liver disease and on ten urine samples from healthy subjects indicated a good correlation.