Bile acid and detergent interaction with radioassays based on coated charcoal.
We tested the radioassays for cyclic AMP and human gastrin, both involving separation on coated charcoal, for interaction with bile acids and detergents, and found a concentration-dependent interaction of taurocholic and glycocholic acid as well as of the surfactant Triton X-100 and sodium laurylsulfate in both assays. The interaction was detectable from concentrations of 0.5 mmol of bile acid per liter or 625 mg of detergent per liter, giving rise to falsely decreased gastrin values and falsely increased or decreased values for cyclic AMP. The interactions demonstrated may be a general effect on all radioassays that are based on the use of coated charcoal in the separation of free from bound ligands.
D001647:Bile Acids and Salts; D002606:Charcoal; D000242:Cyclic AMP / Q000032:analysis*; D003902:Detergents; D005069:Evaluation Studies as Topic; D005755:Gastrins / Q000032:analysis*; D006801:Humans; D011786:Quality Control; D011869:Radioligand Assay / Q000379:methods
D001647:Bile Acids and Salts; D003902:Detergents; D005755:Gastrins; D002606:Charcoal; D000242:Cyclic AMP