IDK Faecal Bile Acids ELISA


The IDK® Bile Acids test is a photometric assay for the quantitative determination of bile acids in stool samples. In the presence of excess thio-NAD, bile acids are converted to 3-keto steroids by the enzyme 3-alpha-hydroxysteroid dehydrogenase while thio-NADH is formed. The rate of at which thio-NADH is formed is determined by the change in absorbance at 405nm over time.

To quantify the concentration of bile acids in stool, an stool extract is prepared using IDKextract, followed by the assay. A dose response curve of change in OD is plotted against the concentration of known standards so that the concentration of bile acids in the samples can be determined.

This fast and innovative assay for the determination of total bile acids in stool samples can help diagnose bile acid diarrhoea in patients with diarrhoea predominant IBS (D-IBS) or be used to support the differential diagnosis.


  • 96 well microplate photometric assay

  • Total assay incubation time 6 minutes

  • Ready to use reagents

  • 6 calibrators

  • 2 controls

  • Capacity for 40 samples in duplicate

  • IDK Extract® universal stool extraction buffer

  • Rapid Extraction Tubes (Stool Sample Application System)


  • Quantifies total faecal bile acids

  • Supports the diagnosis of Bile Acid Malabsorption

  • Useful follow-on test for negative Faecal Calprotectin in patients with diarrhoea

  • Requires a single stool sample collected at home

  • No radiation dose for patients

  • Rapid turnaround

  • One extract can be used in multiple assays (e.g. Calprotectin, Pancreatic Elastase, FIT)