Glycochenodeoxycholic acid (GCDCA) is a glycine-conjugated form of the primary bile acid chenodeoxycholic acid .¹ It reduces formation of cholic acid in primary human hepatocytes when used at a concentration of 100 µM.² GCDCA (50, 75, and 100 µM) reduces the number of LC3 puncta, a marker of autophagy, and is cytotoxic to L-02 hepatocytes.¹ GCDCA (50 µM) induces apoptosis in isolated rat hepatocytes, an effect that can be blocked by the protein kinase C (PKC) inhibitor chelerythrine .³ Fecal levels of GCDCA are decreased in a rat model of high-fat diet-induced obesity compared with rats fed a normal diet.⁴ Glycochenodeoxycholic acid MaxSpec® standard is a quantitative grade standard of glycochenodeoxycholic acid that has been prepared specifically for mass spectrometry and related applications where quantitative reproducibility is required. The solution has been prepared gravimetrically and is supplied in a deactivated glass ampule sealed under argon. The concentration was verified by comparison to an independently prepared calibration standard. The verified concentration is provided on the certificate of analysis. This Glycochenodeoxycholic acid MaxSpec® standard is guaranteed to meet identity, purity, stability, and concentration specifications and is provided with a batch-specific certificate of analysis. Ongoing stability testing is performed to ensure the concentration remains accurate throughout the shelf life of the product. Note: The amount of solution added to the vial is in excess of the listed amount. Therefore, it is necessary to accurately measure volumes for preparation of calibration standards. Follow recommended storage and handling conditions to maintain product quality.