1、BSI Standards Publication PD ISO/TR 79:2015 Reference materials Examples of reference materials for qualitative propertiesPD ISO/TR 79:2015 PUBLISHED DOCUMENT National foreword This Published Document is the UK implementation of ISO/TR 79:2015. The UK participation in its preparation was entrusted t
2、o Technical Committee RMI/1, Reference Materials. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British
3、 Standards Institution 2015. Published by BSI Standards Limited 2015 ISBN 978 0 580 68968 0 ICS 71.040.30 Compliance with a British Standard cannot confer immunity from legal obligations. This Published Document was published under the authority of the Standards Policy and Strategy Committee on 30 J
4、une 2015. Amendments issued since publication Date Text affectedPD ISO/TR 79:2015 ISO 2015 Reference materials - Examples of reference materials for qualitative properties Matriaux de rfrence - Exemples de matriaux de rfrence pour les proprits qualitatives TECHNICAL REPORT ISO/TR 79 Reference number
5、 ISO/TR 79:2015(E) First edition 2015-04-15PD ISO/TR 79:2015ISO/TR 79:2015(E)ii ISO 2015 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2015 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electro
6、nic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. +
7、41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in SwitzerlandPD ISO/TR 79:2015ISO/TR 79:2015(E)Foreword v Introduction vi 1 Scope . 1 2 R efer enc e mat erials c ertified for their DN A sequenc e . 1 2.1 General . 1 2.2 Selected examples of certified referenc
8、e materials . 1 2.3 Certification approaches applied 2 2.3.1 Processing of the materials . 2 2.3.2 Purity assessment . 3 2.3.3 Genomic DNA CRMs 4 2.3.4 Characterization (leading to certified values) 4 2.3.5 Additional characterization (leading to non-certified values) . 4 2.3.6 Suitability study 4 2
9、.3.7 Homogeneity study 5 2.3.8 Minimum sample intake 5 2.3.9 Short-term and long-term stability 5 2.3.10 Identification probability . 6 2.3.11 Documentary and metrological traceability 6 3 Organic reference materials for qualitative analysis . 6 3.1 General . 6 3.2 Verification of the identification
10、 of a marker for steroid abuse . 7 3.3 The added value of knowing the synthetic procedure 9 4 Biospecimens of human origin, c ertified for qualitati v e pr operties .10 4.1 General 10 4.2 Selected human biospecimen examples of reference materials 10 4.3 Certification approaches applied .11 4.3.1 Gen
11、eral.11 4.3.2 Processing of the materials 11 4.3.3 Purity assessment 11 4.3.4 Characterization 12 4.3.5 Suitability study .15 4.3.6 Homogeneity study .16 4.3.7 Stability study 16 4.4 Conclusion on biospecimens as reference material certified for qualitative properties .16 4.4.1 General.16 4.4.2 Docu
12、mentary and metrological traceability .17 5 Reference material for darnel seed identity 17 5.1 General 17 5.2 Preparation of the reference materials .17 5.3 Intended use .18 5.4 Characterization .18 5.4.1 Qualitative property to be characterized .18 5.4.2 Principal of characterization 18 5.4.3 Chara
13、cterization of the reference material for darnel seed identity .24 5.5 Homogeneity and stability study .28 5.6 Uncertainty 28 5.7 Expressing the qualitative property of the reference material 28 5.8 Traceability .28 6 C olour of fr esh w at er cultur ed pear ls .29 6.1 General 29 6.2 Homogeneity tes
14、ting .29 7 E ur opean Pharmac opoeia r efer enc e standar ds for qualitati v e anal y sis32 ISO 2015 All rights reserved iii Contents PagePD ISO/TR 79:2015ISO/TR 79:2015(E)7.1 General 32 7.2 Examples .32 7.2.1 European Pharmacopoeia reference standards for confirmation of identity of a substance for
15、 pharmaceutical use by infrared spectrophotometry .32 7.2.2 European Pharmacopoeia reference standards used for identification by nuclear magnetic resonance spectrometry. .34 7.2.3 European Pharmacopoeia reference standards used for identification of impurities by liquid chromatography .34 7.2.4 Est
16、ablishment and production of European Pharmacopoeia reference standards for qualitative use 35 Bibliogr aph y .36 iv ISO 2015 All rights reservedPD ISO/TR 79:2015ISO/TR 79:2015(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
17、 (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations,
18、governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further ma
19、intenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). A
20、ttention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduc
21、tion and/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to con
22、formity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information The committee responsible for this document is ISO/REMCO, Committee on reference materials. ISO 2015 All rights r
23、eserved vPD ISO/TR 79:2015ISO/TR 79:2015(E) Introduction In 2007, ISO/REMCO created an ad hoc group (AHG) to investigate the need for guidance on the production of Reference Material (RM) certified for a qualitative property. AHG 01 carried out a gap analysis, contacting 12 organizations and bodies
24、using qualitative RMs and reviewed 13 documents referring to qualitative RMs. Based on this gap analysis, ISO/REMCO decided in 2008 to create a working group (WG) and to entrust it with the drafting of an ISO document. Due to the limited information submitted in the following years to WG13, the draf
25、ting of internationally harmonized guidance turned out to be impossible. Instead, it was decided to focus on an ISO Technical Report (TR), which summarizes the state of the art of the production of qualitative RMs. This TR lists examples of RMs which are either certified for a qualitative property o
26、r which can be considered as in-house RMs characterized for a qualitative property. Therefore, many of the RM examples listed here are based on the principles elaborated in ISO Guide 35 1and ISO Guide 80. 2The examples represent the experience gathered by various organizations and bodies and their i
27、nterpretation of qualitative properties, but did not undergo a consensus building process. In this TR, the following six RM examples are presented: a) the certification of RMs for their DNA sequences by an ISO Guide 34 3accredited reference material producer (RMP) (Clause 2); b) the in-house charact
28、erization of organic chemicals as RMs for identification purposes b y a laboratory (Clause 3); c) the identification of a RM biospecimen by an ISO/IEC 17020 4accredited tissue bank (Clause 4); d) the development of a reference material for darnel seed identity (Clause 5); e) the classification and b
29、etween-sample homogeneity testing of a freshwater cultured pearl (Clause 6); f) European Pharmacopoeia reference standards for qualitative analysis (Clause 7). The lack of international standardization in the area of qualitative properties has been recognized by several groups. This includes WG 2 of
30、 the Joint Committee for Guides in Metrology (JCGM), officially responsible for the International Vocabulary of Metrology (VIM), 5which investigates updating and expanding the VIM to cover also qualitative properties. As these discussions are on-going, the terminology used in the various examples pr
31、esented in this TR may differ, e.g. some groups refer to qualitative properties as nominal properties. Likewise, no agreement has yet been made on international level if the term measurement is limited to quantitative properties or may as well be used for qualitative properties. To foster the readab
32、ility of this TR, the term qualitative property has been given preference and the term measurement has been restricted to its use in conjunction with quantitative properties, following the recommendations expressed by the majority of ISO/REMCO delegates during their 37th annual meeting in 2014. Due
33、to the lack of common guidance on the production of RMs for qualitative properties, the approaches and understanding of terms properly defined for quantitative properties (e.g. homogeneity and traceability) are differently interpreted and applied for qualitative properties by the various organizatio
34、ns and bodies which contributed to this collection of examples. Likewise, the border between qualitative and quantitative properties is differently interpreted. Ordinal properties are perceived by some groups to be restricted to quantitative properties, while others suggest distinguishing between qu
35、antitative and qualitative order. As the predominant aim of this TR is to contribute to the on-going discussion, these differences were on purpose maintained.vi ISO 2015 All rights reservedPD ISO/TR 79:2015ISO/TR 79:2015(E) During the writing of ISO/TR 79, ISO/REMCO WG 13 identified a number of disc
36、ussion items, which could not yet be answered with consensus, but which are considered to be crucial in case further efforts will be made to transform this TR into a Guide. The expression of confidence related to identification is discussed and in the majority of the cases, no uncertainty is estimat
37、ed, although experts agree that the probability for a wrong identification forms also part of the result. The identity of an object does not have an uncertainty; however, the assessment of the identity of an object is related to the possibility for misclassification. Ways to estimate the uncertainty
38、 of qualitative analysis are especially suggested in the area of DNA sequencing. 6At the same time, several areas require an assessment uncertainty equaling zero, like e.g. the classification of blood group values. 7 Forward/backward DNA sequencing is considered by many experts as an orthogonal meth
39、od or method free of parameters influencing the result. At the same time, the question is asked what makes DNA sequencing specific. Heterogeneity of materials used as RM for qualitative property identification does not necessarily ruin the intended use. Ways are needed to check to which extend for i
40、nstance inhomogeneity can be accepted. A working group at AOAC International developed internationally harmonized guidelines for the validation of qualitative binary chemistry methods. 8The Guidelines for Validation of Qualitative Binary Chemistry Methods approach the question from the view point of
41、 the method. The question whether the RM used in presence/absence testing needs to be certified for a quantitative or qualitative property has not been discussed in this working group so far. ISO 2015 All rights reserved viiPD ISO/TR 79:2015PD ISO/TR 79:2015Reference materials - Examples of referenc
42、e materials for qualitative properties 1 Scope This Technical Report summarizes the state of the art of the production and certification or characterization of qualitative property reference materials (RMs). The need for guidance documents for the production of RMs certified for qualitative properti
43、es was recognized by many experts. At the same time, the available information was found to be too immature to develop an internationally accepted guidance document. Additionally, the lack of an international vocabulary for terms and definitions for qualitative properties made it more difficult for
44、the experts from various testing areas to communicate with each other. ISO/TR 79 summarizes the available expertise. It aims to contribute to the on-going discussion on nominal properties and the production of such RMs. The investigation of nominal properties is referred to differently in various sp
45、ecialized areas (examination, classification, identification, testing, observation, etc.). ISO/TR 79 tries to foster the future development of an internationally harmonized guidance document. 2 R efer en c e mat eria ls c ertified for their D N A sequenc e 2.1 General The following is a compilation
46、of the certification approaches applied for three reference materials which were certified for their DNA sequence by the Joint Research Centre of the European Commission, Institute for Reference Materials and Reference Materials (IRMM, Geel, BE). 2.2 S elect ed e x amples of c ertified r efer enc e
47、mat erials CRM ERM-AD427 9is composed of plasmid DNA certified to contain certain DNA fragments. It is used for the quantification of Genetically Modified Organisms (GMOs) and the calibration of a defined quantitative Polymerase Chain Reaction (PCR) method. The Certified Reference Material (CRM) con
48、tains a plasmid carrying two defined 2-deoxyribonucleic acid (DNA) fragments. The plasmid calibrant is certified by DNA sequencing for containing two specific DNA targets per plasmid. The number ratio between the two targets is equal to 1, allowing the use as calibrant for relative real-time PCR mea
49、surements. The DNA sequence identity has been confirmed by dye terminator cycle sequencing with a negligible error probability for the sequence identification. CRM IRMM-448 10is composed of genomic DNA extracted from a microorganism and certified for its DNA identity (with the PCR region of interest verified by DNA sequencing). IRMM-448 is used as positive control in a defined qualitative PCR method for food testing. The CRM consists of a purified and freeze-dried genomic DNA (gDNA) of Campylobacter jejuni (NCTC11351). The
