The Role of Standardization Bodies in the Harmonization of Analytical Methods
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2. Use of commercial products (e.g. PCR systems and ELISA kits). Given the characteristics of any standard mentioned in this section, these products should not be mentioned in specific standards, but need to be validated against the corresponding standard reference method to show they give at least equivalent results, in accordance with the validation protocol of the Standard EN ISO 16140.
IV.B. Use of PCR in food microbiology Use of PCR in food microbiology is covered by the TAG 3 of CEN/TC 275/WG 6 (Table 12.2). This group mainly develops general guidance standards on the use of PCR in this field, and several of them have been published recently in 2005/2006 (Table 12.5). These general guidance standards deal with: general requirements and definitions for qualitative methods, general guidelines on sample preparation, amplification and detection, and performance criteria for thermocyclers. Another standard is currently being prepared to give general guidance on real-time PCR. TAG 3 has been also recently entrusted by WG 6 to develop specific standard methods based on PCR. Currently, three standards are being prepared: one for the detection of neurotoxin genes of Clostridium botulinum, a second for the detection of pathogenic genes of Yersinia enterocolitica, and another for the detection of pathogenic genes of Vibrio.
Table 12.5 List of CEN/ISO standards on the use of PCR for the detection of pathogenic microorganisms in food* Topic
Standard reference numbera
General requirements and definitions
EN ISO 22174: 2005
Sample preparation for qualitative detection
EN ISO 20837: 2006
Amplification and detection for qualitative detection
EN ISO 20838: 2006
Performance testing for thermocyclers
EN ISO/TS 20836: 2005
a ‘EN ISO’ means that a common CEN/ISO Standard is concerned, ‘ISO’ that it is only an ISO Standard. ‘ISO/TS’ means ISO Technical Specification. The year of publication of the last version is indicated after the reference number. * Data obtained from CEN website: http://www.cenorm.be; and ISO website: http://www.iso.org/.