New DiaSys Enzymatic Method for Determination of Total Bile Acids in Serum on a BioMajesty[R] JCA 6010/C Clinical Chemistry Analyzer

• Published in: Indian journal of clinical biochemistry 2022-05, Vol.34 (S1), p.S126
• Main Authors: Delseith, I, Masetto, A, Leber, T, Mueller, H, Runkel, S, Grimmler, M
• Format: Article
• Language: English
• Subjects: Bile acids; Enzymes; Liver; Liver cirrhosis; Methods
• ISSN: 0970-1915

Total bile acid (TBA) content is a sensitive marker of liver function for diagnosis and monitoring of various liver diseases. Increased TBA levels are associated with acute and chronic hepatitis, intrahepatic cholestasis of pregnancy (ICP), liver sclerosis, cirrhosis and cancer. Commercially available assays show limitations regarding the detection of clinically relevant primary and secondary bile acids. DiaSys introduces a new liquid-stable, ready-to-use reagent for assessment of all relevant bile acids in a sample offering the possibility to precisely cover all stages of liver diseases. The enzymatic Total bile acids 21 FS test is based on a specific 3-[alpha]-hydroxysteroid dehydrogenase cycling reaction converting Thio-NAD to Thio-NADH. In a second reaction step, oxidized bile acids are reduced by the same enzyme with subsequent reduction of NADH to NAD. The rate of Thio-NADH formation is determined by a change of absorbance at 410/596 nm, which is directly proportional to the concentration of bile acids in the sample material. Recovery studies on various primary and secondary bile acids were performed using 50 [micro]M aqueous bile acids solutions. In-series precision studies have been performed according to CLSI protocol (EP5-A3). Comparative studies were performed with 100 serum samples. Data have been evaluated by using regression analysis according to Passing and Bablok. Linearity of the new Total bile acids 21 FS test is up to 220 pmol/L. Total bile acids 21 FS shows a very good in-series precision with a CV of [less than or equal to] 0.83% (at 10 [micro]mol/L). Furthermore, method comparison of Total bile acids 21 FS with 100 native samples against a competitor test demonstrated excellent correlation [r = 0.9963; Passing/Bablok: y = 1.026 * + 0.211 pmol/L]. Calibration stability of up to 6 weeks has been achieved for the new test on BioMajesty[R] JCA 6010/C which is a decisive advantage over competition.