6. AOACSPIFANMethods-2018Awards

1128  Mottier et al. : J ournal of AOAC I nternational Vol. 98, No. 4, 2015 tate is also a naturally occurring poison found in at least 40 plants native in nd West Africa and Brazil.

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( 6 )  Microcentrifuge tubes, polypropylene .—2 mL (e.g., Trefflab art. 9607246901; www.treff-ag.ch). ( 7 )  Analytical balance.— With precision range 0.01 mg . ( 8 )  Shaker .—GenoGrinder Model 2010 (www. spexsampleprep.com). ( 9 )  Evaporator .—e.g., Reacti-Vap Evaporator (art. TS-18825; www.thermo.com). ( c )  Special equipment and instrumentation .—Where a specific model is cited, an alternative may be used if it has the same characteristics. ( 1 )  HPLC system .—Agilent 1200 SL (www.agilent. com) coupled to a Sciex 5500 triple stage quadrupole mass spectrometer equipped with a TurboIonSpray ® ionization source (www.sciex.com). ( 2 )  HPLC column .—Acquity UPLC BEH Amide, 2.1 × 100 mm, 1.7 µm (Waters art. 186004801; www.waters.com). ( d )  Glassware decontamination .—No specific requirement. C. Preparation of Reagents Volumes of glassware are purely indicative and may be modified as long as the proportion of reagents is maintained. ( a )  Sodium fluoroacetate stock standard solution, 10 µg/mL in water .—The stock standard solution is available as ready- to-use 10 mL solution. Store at room temperature for the time given in the certificate of analysis. ( b )  Sodium fluoroacetate working standard solution, 1.0 µg/mL in acetonitrile–water (9 + 1).— Into a 10 mL volumetric flask, pipet 1.0 mL of the stock standard solution 10 µg/mL, C ( a) . Complete to volume with acetonitrile. Store at –20°C for no longer than 6 months. Allow warming at room temperature before use. ( c )  Sodium fluoroacetate working standard solution , 0.2 µg/mL in acetonitrile .—Into a 10 mL volumetric flask, pipet 2.0 mL of the stock standard solution 1 µg/mL, C ( b) . Complete to volume with acetonitrile. Store at –20°C for no longer than 6 months. Allow warming at room temperature before use. ( d )  Sodium fluoroacetate working standard solution, 0.05 µg/mL in acetonitrile .—Into a 10 mL volumetric flask, pipet 2.5 mL of the stock standard solution 0.2 µg/mL, C ( c) . Complete to volume with acetonitrile. Store at –20°C for no longer than 6 months. Allow warming at room temperature before use. ( e )  13 C 2 -Sodium fluoroacetate (IS) stock standard solution, 1000 µg/mL in water .—Into a 10 mL volumetric flask, weigh 10 ± 0.1 mg of standard. Dissolve and complete to the mark with water. Alternatively (to minimize analyst exposure during weighing) weigh the container containing the analyte first (w 1 , in mg), then transfer its whole content into a 10 mL volumetric flask. Dissolve and complete to mark with water for chromatography. Weigh again the empty original container once dried (w 2 , in mg). Concentration of this solution in µg/mL is 1000 × (w 1 – w 2 )/10. Store at –20°C for no longer than 6 months. Allow warming at room temperature before use. ( f )  13 C 2 -Sodium fluoroacetate (IS) working standard solution, 10 µg/mL in acetonitrile .—Into a 10 mL volumetric flask, pipet 100 µL of the stock solution 1000 µg/mL, C ( e ). Complete to volume with acetonitrile. Store at –20°C for no longer than 6 months. Allow warming at room temperature before use. ( g )  13 C 2 -Sodium fluoroacetate (IS) working standard solution, 0.2 µg/mL in acetonitrile .—Into a 50 mL volumetric

O F

Chemical structure of sodium fluoroacetate (NaFC 2 H 2 O 2 ; CAS 62-74-8; MW 100 g/mol) ONa

Figure 2015.03A. Chemical structure of sodium fluoroacetate (NaFC 2 H 2 O 2 ; CAS No. 62-74-8; MW 100 g/mol). gure 1.

Quantification is performed by the isotopic dilution approach using 13 C labeled sodium fluoroacetate as internal standard (IS). Positive identification of fluoroacetate in samples is conducted according to the confirmation criteria defined in EU Commission Decision 2002/657/EC (1). B. Chemicals and Materials Commercial references are only a guideline. Use equivalent chemicals or materials when listed items are not locally available. ( a )  Chemicals .—Before using chemicals, refer to the Sigma- Aldrich (www.sigmaaldrich.com) Guide to Chemical Safety and/or other adequate manuals or safety data sheets approved by your local authorities and ensure that the safety guidelines are applied. ( 1 )  Water for chromatography. —CAS No. 7732-18-5 (e.g., Merck LiChrosolv ® art. 15333; www.emdmillipore.com). ( 2 )  Acetonitrile, hypergrade for LC-MS .—CAS No. 75-05-8 (e.g., Merck LiChrosolv art. 100029; www.chemdat.info). ( 3 )  n-Hexane .—For gas chromatography; CAS No. 110-54-3 (e.g., Merck SupraSolv® art. 104371; www.chemdat. info). ( 4 )  QuEChERS extraction packets .—10 g, 200 foil packs per box, each pack containing 4 g magnesium sulfate (MgSO 4 ) and 1 g sodium chloride (NaCl). CAS Nos. 7487-88-9 and 7647-14-5 (e.g., Agilent art. 5982-7550; www.agilent.com). ( 5 )  Ammonium formate .—LC-MS ultra, eluent additive for UHPLC-MS. CAS No. 540-69-2 (e.g., Fluka art. 14266; www. sigmaaldrich.com). ( 6 )  Sulfuric acid .—Concentrated, w = 95–97%. CAS No. 7664-93-9 (e.g., Merck art. 100731; www.merckmillipore.com). ( 7 )  Formic acid .—Concentrated (e.g., Merck art. 100264; www.chemdat.info). CAS No. 64-18-6. ( 8 )  Sodium fluoroacetate .—CAS No. 62-74-8, w = 99%, 10 µg/mL in water (e.g., Dr. Ehrenstorfer art. DRE- L13772000AL; www.lgcstandards.com). ( 9 )  13 C 2 -Sodium fluoroacetate .— w = 99%, isotopic purity >99.5% (e.g., BDG Synthesis art. 130042-10; http://bdg.co.nz). ( b )  Materials .— ( 1 )  Falcon tubes, conical, polypropylene .—50 mL (e.g., Becton Dickinson Labware art. 352070; www.bdbiosciences. com). ( 2 )  Falcon tubes, conical, polypropylene .—15 mL (e.g., Becton Dickinson Labware art. 352097; http://www. bdbiosciences.com). ( 3 )  Centrifuge with rotors adapted for 50 and 15 mL tubes. —4000 × g , temperature controlled (e.g., Multifuge Heraeus; www.thermo.com). ( 4 )  Vortex .—e.g., Millian Genie 2 (http://www.milian.com). ( 5 )  Centrifuge with rotor adapted for 2 mL tubes .—17000 × g (e.g., Heraeus Frisco 17; www.thermoscientific.com).

___________________________________________________________ 1 ive, Scientific Business Development, amishra@aoac.org enior Director, Approv l Processes & AOAC Research Institute, dmckenzie@aoac.org r Director, Publications, rrathbone@aoac.org RNATIONAL