AOAC OMB Final Action Recommendation (December 2019)-2016.14

2016.14 (October 2019) – FOS-03 METHOD

FOR ERP USE ONLY DO NOT DISTRIBUTE

(c) Microtubes. —1.5-mL & 2-mL.

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(d) Floating rack for microtubes.

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(e) Water bath. —Able to maintain 80 °C ± 1 °C, with magnetic stirring if available.

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(f) Water bath. —Able to maintain 40 °C ± 1 °C.

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(g) Microcentrifuge. —Able to operate at 10 000 x g .

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(h) Micropipettes. —With tips (0.1 to 1) mL.

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(i) Vortex mixer .

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(j) Single-use plastic pipettes. —Graduated, 2-mL, 10-mL and 25-mL.

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(k) Single-use syringes. —2-mL.

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(l) Graphitized carbon solid phase extraction (SPE) columns. —100 mg.

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(m) Membrane filter nylon. —0.2 µm, Ø 4.7 cm (only when using PA1 column for HPAEC-PAD).

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(n) Analytical column. —CarboPac PA20 (150 x 3 mm, 6.5 µm) with no guard, or CarboPac PA1

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(250 x 2 mm, 10 µm), with PA1 guard (50 x 2 mm, 10 µm) (Thermo Fisher Scientific, MA USA), or

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equivalent.

(o) Metal free liquid chromatograph consisting of :

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- Quaternary gradient pump able to deliver a flow of 0.5 mL/min (PA20) or 0.25 mL/min (PA1).

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- Helium degassing system.

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- Autosampler (cooling system recommended) able to inject 25 µL (PA20) or 20 µL (PA1).

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- Column compartment able to maintain a temperature of 30 °C (PA20) or 20 °C (PA1).

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- Electrochemical detector working in pulsed amperometric detection mode, equipped with a

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gold working electrode and an Ag/AgCl reference electrode (or equivalent).

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