standard/isotope

Octanoic acid-13C is intended for use as an internal standard for the quantification of octanoic acid by GC- or LC-MS. Octanoic acid is a medium-chain saturated fatty acid. It has been found in Teleme cheeses made from goat, ovine, or bovine milk.1 Octanoic acid is active against the bacteria S. mutans, S. gordonii, F. nucleatum, and P. gingivalis (IC80s = <125, <125, 1,403, and 2,294 μM, respectively).2 Levels of octanoic acid are increased in the plasma of patients with medium-chain acyl-CoA dehydrogenase (MCAD) deficiency, an inborn error of fatty acid metabolism characterized by hypoketotic hypoglycemia, medium-chain dicarboxylic aciduria, and intolerance to fasting.3,4 |1. Mallatou, H., Pappa, E., and Massouras, T. Changes in free fatty acids during ripening of Teleme cheese made with ewes', goats', cows' or a mixture of ewes' and goats' milk. Int. Dairy J. 13(1-3), 211-219 (2003).|2. Hyang, C.B., Alimova, Y., Myers, T.M., et al. Short- and medium-chain fatty acids exhibit antimicrobial activity for oral microorganisms. Arch. Oral Biol. 56(7), 650-654 (2011).|3. Onkenhout, W., Venizelos, V., van der Poel, P.F.H., et al. Identification and quantification of intermediates of unsaturated fatty acid metabolism in plasma of patients with fatty acid oxidation disorders. Clin. Chem. 41(10), 1467-1474 (1995).|4. Rinaldo, P., O'Shea, J.J., Coates, P.M., et al. Medium-chain acyl-CoA dehydrogenase deficiency. Diagnosis by stable-isotope dilution measurement of urinary n-hexanoylglycine and 3-phenylpropionylglycine. N. Engl. J. Med. 319(20), 1308-1313 (1988).

HT-2 toxin-13C22is intended for use as an internal standard for the quantification of HT-2 toxin by GC- or LC-MS. HT-2 toxin is a type A trichothecene mycotoxin and an active, deacetylated metabolite of the trichothecene mycotoxin T-2 toxin .1,2Like T-2 toxin, HT-2 toxin inhibits protein synthesis and cell proliferation in plants.2HT-2 toxin also reduces viability of HepG2, A549, HEp-2, Caco-2, A-204, U937, Jurkat, and RPMI-8226 cancer cells with IC50values ranging from 3.1 to 23 ng/ml and human umbilical vein endothelial cells with an IC50value of 56.4 ng/ml.1It induces oxidative stress, DNA damage, and autophagy in, as well as halts the development of, cultured mouse embryos when used at a concentration of 10 nM.3HT-2 toxin has been found in cereal grains and food products.4,5 1.Nielsen, C., Casteel, M., Didier, A., et al.Trichothecene-induced cytotoxicity on human cell linesMycotoxin Res.25(2)77-84(2009) 2.Nathanail, A.V., Varga, E., Meng-Reiterer, J., et al.Metabolism of the fusarium mycotoxins T-2 toxin and HT-2 toxin in wheatJ. Agric. Food Chem.63(35)7862-7872(2015) 3.Zhang, L., Li, L., Xu, J., et al.HT-2 toxin exposure induces mitochondria dysfunction and DNA damage during mouse early embryo developmentReprod. Toxicol.85104-109(2019) 4.Langseth, W., and Rundberget, T.The occurrence of HT-2 toxin and other trichothecenes in Norwegian cerealsMycopathologia147(3)157-165(1999) 5.Al-Taher, F., Cappozzo, J., Zweigenbaum, J., et al.Detection and quantitation of mycotoxins in infant cereals in the U.S. market by LC-MS/MS using a stable isotope dilution assayFood Control72(Part A)27-35(2017)

Nicotinamide-d4是Nicotinamide的氘代标记化合物，可用于同位素示踪。Nicotinamide是一种维生素B3的衍生物，是SIRT1和SIRT2的抑制剂。

Clozapine-d8是抗精神病化合物氯氮平的氘代标记类似物，其分子中八个氢原子被稳定同位素氘取代。与母体分子类似，Clozapine-d8可作为D4多巴胺受体和5HT2血清素受体的选择性配体，这使Clozapine-d8成为质谱定量分析氯氮平的重要内标。氯氮平是一种主要用于治疗耐药性精神分裂症研究的非典型抗精神病药物，除主要靶点外还对多种神经受体具有高亲和力。

U-[13C17]-Aflatoxin M2 in Acetonitrile (Standard)(U-[13C17]-黄曲霉毒素 M2 溶于乙腈 (标准品))是全13C同位素标记的黄曲霉毒素M2溶液，可用作分析标准品，测定样品中的黄曲霉毒素M2。