title: Simultaneous determination of 3-mercaptopyruvate and cobinamide in plasma by liquid chromatography-tandem mass spectrometry.
abstract: The current suite of Food and Drug Administration (FDA) approved antidotes (i.e., sodium nitrite, sodium thiosulfate, and hydroxocobalamin) are effective for treating cyanide poisoning, but individually, each antidote has major limitations (e.g., large effective dosage or delayed onset of action). To mitigate these limitations, next-generation cyanide antidotes are being investigated, including 3-mercaptopyruvate (3-MP) and cobinamide (Cbi). Analytical methods capable of detecting these therapeutics individually and simultaneously (for combination therapy) are essential for the development of 3-MP and Cbi as potential cyanide antidotes. Therefore, a liquid chromatography-tandem mass-spectrometry method for the simultaneous analysis of 3-MP and Cbi was developed. Sample preparation of 3-MP consisted of spiking plasma with an internal standard ((13)C3-3-MP), precipitation of plasma proteins, and derivatizing 3-MP with monobromobimane to produce 3-mercaptopyruvate-bimane. Preparation of Cbi involved denaturing plasma proteins with simultaneous addition of excess cyanide to convert each Cbi species to dicyanocobinamide (Cbi(CN)2). The limits of detection for 3-MP and Cbi were 0.5μM and 0.2μM, respectively. The linear ranges were 2-500μM for 3-MP and 0.5-50μM for Cbi. The accuracy and precision for 3-MP were 100±9% and <8.3% relative standard deviation (RSD), respectively. For Cbi(CN)2, the accuracy was 100±13% and the precision was <9.5% RSD. The method presented here was used to determine 3-MP and Cbi from treated animals and may ultimately facilitate FDA approval of these antidotes for treatment of cyanide poisoning.
authors.affiliation: Department of Chemistry and Biochemistry, South Dakota State University, Avera Health and Science Center 131, Box 2202, Brookings, SD 57007, United States.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Stutelberg
authors.affiliation: Department of Chemistry and Biochemistry, South Dakota State University, Avera Health and Science Center 131, Box 2202, Brookings, SD 57007, United States.
authors.forename: Joseph K
authors.initials: JK
authors.lastname: Dzisam
authors.affiliation: Center for Drug Design, University of Minnesota, 516 Delaware Street SE, Minneapolis, MN 55455, United States.
authors.forename: Alexandre R
authors.initials: AR
authors.lastname: Monteil
authors.affiliation: Department of Chemistry, Sam Houston State University, P.O. Box 2117, Huntsville, TX 77341, United States.
authors.forename: Ilona
authors.initials: I
authors.lastname: Petrikovics
authors.affiliation: Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States.
authors.forename: Gerry R
authors.initials: GR
authors.lastname: Boss
authors.affiliation: Center for Drug Design, University of Minnesota, 516 Delaware Street SE, Minneapolis, MN 55455, United States.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Patterson
authors.affiliation: Analytical Toxicology Division, US Army Medical Research Institute of Chemical Defense, 3100 Rickets Point Road, Aberdeen Proving Ground, MD 21010, United States.
authors.forename: Gary A
authors.initials: GA
authors.lastname: Rockwood
authors.affiliation: Department of Chemistry and Biochemistry, South Dakota State University, Avera Health and Science Center 131, Box 2202, Brookings, SD 57007, United States. Electronic address: brian.logue@sdstate.edu.
authors.forename: Brian A
authors.initials: BA
authors.lastname: Logue
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods*; D003038:Cobamides / Q000097:blood*; D003545:Cysteine / Q000031:analogs & derivatives* / Q000097:blood; D057230:Limit of Detection; D013552:Swine; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D003038:Cobamides; C017142:cobinamide; C008366:3-mercaptopyruvic acid; D003545:Cysteine
keywords: Cyanide antidote; Mass spectrometry; Sulfanegen