# Commission Regulation (EC) No 152/2009 of 27 January 2009 laying down the methods of sampling and analysis for the official control of feed (Text with EEA relevance), Division 5.3.1: Parameters

Extent: E+W+S+N.I.

The following conditions are offered for guidance, other conditions may be used provided that they give equivalent results.
Liquid chromatographic column (4.2.1)
100 mm × 4,6 mm, Hypersil ODS, 3 μm packing, or equivalent
Mobile phase:
Eluent A (3.13.1):
Aqueous solution of ammonium acetate and tetrabutyl-ammonium hydrogen sulphate
Eluent B (3.13.2):
acetonitrile
Eluent C (3.13.3):
methanol
Elution mode:
linear gradient
initial conditions: A + B + C = 60 + 20 + 20 (V + V + V)
after 10 min. gradient elution during 30 min. to: A + B + C = 45 + 20 + 35 (V + V + V)
Flush with B during 10 min.
Flow rate:
1,5-2 ml/min.
Injection volume:
20 μl
Detector wavelength:
280 nm.
Check the stability of the chromatographic system, injecting several times the calibration solution (3.10), containing 2 μg/ml, until constant peak heights and retention times are achieved.

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Source: https://www.legislation.gov.uk/eur/2009/152/annex/IV/division/F/division/5/division/5.3/division/5.3.1 (the official version)
Page: https://openlegislation.uk/eu-regulation-2009-152/annex-IV/division-F/division-5/division-5.3/division-5.3.1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.