6. AOACSPIFANMethods-2018Awards

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Reddy: J ournal of AOAC I nternational V ol. 98, N o . 4, 2015  1135

OFFICIAL METHODS

Determination of Monofluoroacetate in Powdered Nutritional Products by Derivatization with 2-Nitrophenylhydrazine and LC-MS/MS: First Action

2015.04 Murali Reddy Abbott Laboratories, 3300 Stelzer Rd, Columbus, OH 43219 Stakeholder Panel on Infant Formula and Adult Nutritionals Expert Review Panel for Working Group for Sodium Fluoroacetate Darryl Sullivan (Chair) , Covance Martin Alewijn , RIKILT John Austad , Covance Joe Boison , CFIA/Univ of Saskatoon Scott Christiansen , Perrigo Jo Marie Cook , Florida State Dept of Agriculture Jon DeVries , Medallion Labs/General Mills Harvey Indyk , Fonterra George Joseph , AsureQuality Erik Konings , Nestle Alex Krynitsky , U.S. Food and Drug Administration Tom Phillips ,Maryland State Dept of Agriculture Bert Popping , Merieux NutriSciences Murali Reddy , Abbott John Wong , U.S. Food and Drug Administration

[Applicable of monofluoroacetate (MFA) in powdered nutritional product.] Caution : Monofluoroacetate is highly toxic and volatile below pH 4. Acetonitrile, ethyl acetate, and pyridine are toxic and flammable. Hydrochloric acid is toxic and corrosive. A. Principle The method incorporates certain elements from refs (1) and (2). Samples are prepared by dilution in water followed by protein precipitation with acetonitrile. An aliquot of the sample extract is derivatized with 2-nitrophenylhydrazine (2- NPH) in the presence of 1-ethyl-3-(-3-dimethylaminopropyl) carbodiimide hydrochloride (EDC). This reaction achieves the coupling of the carboxyl group of monofluoroacetate to the amino group of 2-NPH with the formation of an amide bond. Samples are processed through a solid-phase extraction (SPE) step in order to exchange sample solvent and achieve a 5-fold concentration of the extract. A stable-isotope labeled internal standard is incorporated into the sample preparation to correct for instrument response and losses in sample preparation. Analysis is performed by ultra-high pressure liquid chromatography (UPLC) coupled to tandem quadrupole mass spectrometry (MS/ MS). The MS/MS system is configured to monitor one parent- daughter (precursor-fragment) ion pair for the analyte and internal standard, respectively ( see Figure 2015.04A ). B. Apparatus ( a )  Balance .—Analytical. ( b )  Balance.— Micro-analytical. ( c )  Beakers .—Various sizes. ( d )  Glass bottles .—100 and 500 mL. ( e )  Graduated cylinders .—10 and 100 mL. ( f )  Flasks, volumetric, glass .—Class A; 10, 25, and 100 mL. ( g )  Vortex mixer .—Vortex-Genie (Cole-Parmer, http://www. coleparmer.ca), or equivalent. for quantitative determination

Submitted for publication March 2015. Adopted as a First Action Official Method by the Expert Review Panel on Sodium Fluoroacetate and approved by the Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN).

Figure 2015.04A. Monofluoroacetate C 2 H 2 FO 2

, MW =

Approved on: March 16, 2015. DOI: 10.5740/jaoac.int.2015.04

77.03, CAS No. 62-74-8.