# Commission Decision of 12 August 2002 implementing Council Directive 96/23/EC concerning the performance of analytical methods and the interpretation of results (notified under document number C(2002) 3044) (Text with EEA relevance) (2002/657/EC), Division 2.3.5.1: Chromatographic separation

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

An internal standard shall be used if a material suitable for this purpose is available. It shall preferably be a related standard with a retention time close to that of the analyte. The analyte shall elute at the retention time that is typical for the corresponding calibration standard under the same experimental conditions. The minimum acceptable retention time for an analyte shall be two times the retention time corresponding to the void volume of the column. The ratio of the retention time of the analyte to that of the internal standard, i.e. the relative retention time of the analyte, shall be the same as that of the calibration standard in the appropriate matrix, within a margin of ± 2,5 %.

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Source: https://www.legislation.gov.uk/eudn/2002/657/annex/chapter/2.3/division/2.3.5.1 (the official version)
Page: https://openlegislation.uk/eu-decision-2002-657/annex/chapter-2.3/division-2.3.5.1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.