Related Experiment Video
Updated: Mar 25, 2026

Failure of Cleaning Verification in Pharmaceutical Industry Due to Uncleanliness of Stainless Steel Surface
Published on: August 11, 2017
Limited sample stability of chenodeoxycholic acid in pharmaceutical quality control
Natalja Bouwhuis1,2, Bart A W Jacobs3,2, E Marleen Kemper3,2
1Pharmacy and Clinical Pharmacology, Amsterdam UMC Locatie AMC, Amsterdam, Netherlands n.bouwhuis@amsterdamumc.nl.
None:
The Amsterdam UMC makes chenodeoxycholic acid (CDCA) capsules to treat their patients with the rare metabolic disease cerebrotendinous xanthomatosis. During routine quality control analysis of the CDCA active pharmaceutical ingredient according to the European Pharmacopoeia (PhEur), an unknown impurity was found in the test results for related substances. After re-analysis using a fresh sample solution, the impurity was not detected, and it was hypothesised that the impurity was caused by sample instability. Sample stability was investigated using the PhEur high pressure liquid chromatography with refractive index detection (HPLC-RI) test for related substances on different CDCA sample solutions (dissolved in methanol R) stored for 0, 1, 3 and 7 days at 5°C and 25°C. An unknown impurity appeared when stored for 1 day and its concentration increased over time and at a higher temperature, conforming sample instability. It is recommended to perform the test on related substances of CDCA with a fresh sample solution.
Related Concept Videos
Drug Product Stability
Pharmaceutical Alternatives: Stability-Related Therapeutic Nonequivalence
Bioavailability Enhancement: Drug Stability Enhancement and GI Retention
Factors Affecting Dissolution: Drug Permeability, Stability and Stereochemistry
Clinically Relevant Drug Product Specifications: Methods of Establishment

