Tauroursodeoxycholic acid-d₄(TUDCA-d₄) is intended for use as an internal standard for the quantification of tauroursodeoxycholic acid by GC- or LC-MS. TUDCA is a taurine-conjugated form of the secondary bile acid ursodeoxycholic acid .^1,2TUDCA is found in small quantities in human bile but at a higher concentration in the bile of black bears.²It demonstrates anti-apoptotic activity in rodent models of tauopathy, Huntington's disease, ischemic brain injury, and retinal disorders.^3,2

TUDCA-d₄MaxSpec? Standard is a quantitative grade standard of TUDCA-d₄that has been prepared specifically for mass spectrometry or any application 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 TUDCA-d₄MaxSpec? standard is guaranteed to meet identity, purity, and stability 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.

1.Beuers, U.Effects of bile acids on hepatocellular signaling and secretionYale J. Biol. Med.70(4)341-346(1997) 2.Boatright, J.H., Nickerson, J.M., Moring, A.G., et al.Bile acids in treatment of ocular diseaseJ. Ocul. Biol. Dis. Infor.2(3)149-159(2009) 3.Vang, S., Longley, K., Steer, C.J., et al.The unexpected uses of urso- and tauroursodeoxycholic acid in the treatment of non-liver diseasesGlob. Adv. Health Med.3(3)58-69(2014)