1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 12787:2011Cosmetics Analyticalmethods Validation criteriafor analytical results usingchromatographic techniquesBS ISO 12787:2011 BRITISH STANDARDNational forewordThis Brit
2、ish Standard is the UK implementation of ISO 12787:2011. The UK participation in its preparation was entrusted to T e c h n i c a l Committee CW/217, Cosmetics.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to inclu
3、de all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2012 ISBN 978 0 580 67278 1 ICS 71.100.70 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the
4、 authority of the Standards Policy and Strategy Committee on 31 January 2012.Amendments issued since publicationDate T e x t a f f e c t e dBS ISO 12787:2011Reference numberISO 12787:2011(E)ISO 2011INTERNATIONAL STANDARD ISO12787First edition2011-12-15Cosmetics Analytical methods Validation criteria
5、 for analytical results using chromatographic techniques Cosmtiques Mthodes analytiques Critres de validation pour les rsultats analytiques utilisant des techniques chromatographiques BS ISO 12787:2011ISO 12787:2011(E) COPYRIGHT PROTECTED DOCUMENT ISO 2011 All rights reserved. Unless otherwise speci
6、fied, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Ca
7、se postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2011 All rights reservedBS ISO 12787:2011ISO 12787:2011(E) ISO 2011 All rights reserved iiiContents Page Foreword iv 1 Scope 1 2 Terms and definitions
8、. 1 2.1 General . 1 2.2 Terms relating to validation criteria for analytical results 2 3 Principle . 3 4 General information 4 4.1 Matrix effect . 4 4.2 Decision tree 5 5 First step Minimum validation criteria on standard solutions . 6 5.1 General . 6 5.2 Estimation of detection and quantification l
9、imit in solvent (optional) . 6 5.3 Analytical conformity 7 5.4 Calibration: precision, linearity and accuracy . 7 6 Second step Sample screening . 8 6.1 General . 8 6.2 Sample screening 8 7 Third step Assays . 8 7.1 General . 8 7.2 Analytes not detected or detected at concentrations less than the Lo
10、Q 9 7.3 Analytes detected at a concentration greater than the LoQ . 9 8 Summary 11 Annex A (informative) Example of selection of a weighting factor 12 Annex B (normative) Assays with a target value (simplified approach) . 13 Bibliography 14 BS ISO 12787:2011ISO 12787:2011(E) iv ISO 2011 All rights r
11、eservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (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 wh
12、ich a technical committee has been established has the right to be represented on that committee. International organizations, 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
13、matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are ci
14、rculated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention 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 respo
15、nsible for identifying any or all such patent rights. ISO 12787 was prepared by Technical Committee ISO/TC 217, Cosmetics. BS ISO 12787:2011INTERNATIONAL STANDARD ISO 12787:2011(E) ISO 2011 All rights reserved 1Cosmetics Analytical methods Validation criteria for analytical results using chromatogra
16、phic techniques 1 Scope This International Standard defines validation criteria with which analytical results obtained from the analysis of cosmetic products should comply in order to give confidence in performance, reliability and quality of the final result. It sets out an analytical approach that
17、 can be used by a single laboratory to carry out chromatographic analyses on a given sample, or samples. 2 Terms and definitions For the purposes of this document, the following terms and definitions apply. 2.1 General 2.1.1 analyte substance being subjected to analysis 2.1.2 bias difference between
18、 the expectation of the test results and an accepted reference value 2.1.3 recovery ratio between the quantity of analyte found by a particular analytical method compared to the quantity of analyte expected 2.1.4 post-extraction spiked matrix standards PoEMS samples taken through the entire extracti
19、on procedure and spiked with the analyte of interest at the end of the extraction immediately before, or very close to, detection NOTE PoEMS are also called “Matrix-Matched Standards” or “Fortified Analytical Solutions (FAS)” and are used for determination of the bias. 2.1.5 pre-extraction spiked ma
20、trix standards PrEMS samples spiked with the analyte of interest at the beginning of the analytical procedure NOTE PrEMS are also called “Spikes” or “Fortified Analytical Portions (FAP)” and are used for calibration and quantification of the target analytes in samples (extraction recovery). 2.1.6 ma
21、trix effect combined effect of the presence of one or more components of a sample other than the analyte on the measured quantity of the analyte NOTE The matrix effect could increase or decrease the chromatographic peak area for a same analyte concentration. BS ISO 12787:2011ISO 12787:2011(E) 2 ISO
22、2011 All rights reserved2.1.7 extraction yield ratio between the quantity of analyte extracted during the extraction process from the sample matrix compared to the quantity of analyte present in the sample 2.1.8 solvent standard calibration curve analyte calibration curve obtained from the analyses
23、of at least five different standard calibration levels prepared in the solvent 2.1.9 control standard independent standard solution used to verify the solvent standard calibration curve 2.2 Terms relating to validation criteria for analytical results 2.2.1 accuracy closeness of agreement between a t
24、est result (the average value obtained from a large series of test results) and an accepted reference value NOTE The accuracy is often expressed in terms of bias. 2.2.2 LoD limit of detection lowest amount of an analyte that can be reliably distinguished from zero with reasonable statistical certain
25、ty 2.2.3 LoQ limit of quantification lowest amount of an analyte that can be determined with an acceptable level of uncertainty under the stated conditions of test 2.2.4 linearity ability of the method to obtain test results proportional to the concentration of the analyte 2.2.5 measurement uncertai
26、nty MU parameter, associated with the result of a measurement, that characterizes the dispersion of values that could be reasonably attributed to the measurand 2.2.6 precision closeness of agreement between independent test results obtained under stipulated conditions NOTE Precision depends only on
27、the distribution of random errors and does not relate to the true value or the specified value. 2.2.7 working range interval between the upper and lower concentration (amounts) of analyte in the sample for which it has been demonstrated that the analytical procedure has a suitable level of certainty
28、 2.2.8 repeatability precision under repeatability conditions where independent test results are obtained with the same method on identical test items in the same laboratory by the same operator using the same equipment within short intervals of time BS ISO 12787:2011ISO 12787:2011(E) ISO 2011 All r
29、ights reserved 32.2.9 intermediate precision precision under conditions where independent test results are obtained with the same method on identical test items in the same laboratory by different operators using different equipment on different days 2.2.10 reproducibility precision under reproducib
30、ility conditions, i.e. conditions where independent test results are obtained with the same method on identical test items from different laboratories at different times 2.2.11 selectivity ability of a method to determine accurately and specifically the analyte of interest in the presence of other c
31、omponents in a sample matrix under the stated conditions of the test 2.2.12 sensitivity change in the response of a measuring instrument divided by the corresponding change in the stimulus 2.2.13 specificity ability of a method to measure only what is intended to be measured 2.2.14 target concentrat
32、ion analyte concentration used as a reference for the determination of the analyte concentration in the sample 2.2.15 validation confirmation of examination and provision of objective evidence that the particular requirements for a specified intended use are met 2.2.16 asymmetry factor describing th
33、e shape of a chromatographic peak NOTE The theory assumes a Gaussian shape and that peaks are symmetrical. 2.2.17 resolution ability of a column to separate chromatographic peaks, usually expressed in terms of the separation of two peaks 3 Principle The ingredients of cosmetic products are variable
34、and complex, mainly due to the type of formulation. General analytical methods exist, or are to be developed, to assess the quality of cosmetics. These generalized methods, some of which might not be strictly certifiable, are intended to be widely usable, comprehensible and transferable. The applica
35、tion of analytical methods to cosmetic products requires a specific validation approach in order to ensure the reliability of the results. For cosmetic products, the choice and use of a general method for analytical testing has to be supported by validation criteria specific to the sample matrix in
36、order to ensure the reliability of the results. In this context, this International Standard aims to propose specific validation criteria to be evaluated for the use of a general method for testing cosmetic products. Validation criteria for analytical results to be evaluated include specificity, sel
37、ectivity, recovery, confidence interval, limit of detection, limit of quantification, precision, accuracy and linearity. Validation criteria shall be determined for each sample matrix. If a similar matrix is used, validation criteria need only be determined on the samples first analysed and extended
38、 to other samples in the same concentration range. Accordingly, this approach would not necessarily be applied in routine testing of cosmetic products if validation criteria were previously obtained. Careful consideration should be given to the sample matrix when determining if additional validation
39、 is required. BS ISO 12787:2011ISO 12787:2011(E) 4 ISO 2011 All rights reserved4 General information 4.1 Matrix effect If the sample were submitted to an extraction process before injection (e.g. liquid-liquid extraction or solid-phase extraction), the recovery obtained on the PrEMS, using the solve
40、nt calibration curve, would include both the sample matrix effect and the extraction yield of the process. From an analytical point of view, it would be interesting to distinguish the matrix effect from the extraction yield resulting from the sample preparation (extraction of the analyte from the co
41、smetic matrix). Use of a PoEMS would allow one to distinguish between the matrix effect and the extraction yield. Figure 1 indicates the importance of preparing a PoEMS, in addition to a PrEMS and a standard calibration curve, in order to obtain different validation criteria on the analytical result
42、s, such as the extraction yield and/or the matrix effect. Extraction yield+ matrix effectSolvent standard calibration curveMatrix effectPrEMSExtraction yieldPoEMSValidation criteria purposeFigure 1 Validation criteria for analytical results obtained using PrEMS, PoEMS and a solvent calibration curve
43、 If an extraction process is performed, the matrix effect is given by the PoEMS recovery (using the solvent standard calibration curve). The difference between PoEMS and PrEMS recoveries gives the extraction yield of the sample process. If no extraction process is performed, the extraction yield is
44、equal to 100 %, and the matrix effect is given by the PrEMS (or PoEMS) recovery. If the recovery obtained on PrEMS, using the solvent standard calibration curve, is significantly different from the expected value, a matrix effect should be suspected. Under these circumstances, it is recommended that
45、 the method of standard addition be used. PrEMS and PoEMS preparations should be carried out under the following conditions: use a solvent compatible with the sample preparation; use the minimum possible amount of solvent to introduce the analyte in the test solution; depending on the sample type, s
46、piked samples (PrEMS) should be prepared by mixing the analyte solution with the sample, allowing dispersion into liquid samples and penetration/adsorption onto non-liquid or solid samples (this step should be adapted if the analyte is highly volatile); perform the PrEMS and the PoEMS at the estimat
47、ed analyte concentration within the calibration range. BS ISO 12787:2011ISO 12787:2011(E) ISO 2011 All rights reserved 5This analytical approach should only be used if the compound added to the cosmetic matrix behaves similarly to the compound present in the matrix. If not, certified or well-charact
48、erized standard samples could be proposed as an alternative. Careful consideration should be given to the use of spiked samples with solid cosmetic products. 4.2 Decision tree The decision tree, represented in Figure 2, indicates the proposed approach and the different steps to be performed. Check s
49、ome validation criteria on standard solutions (See Clause 5)Aim: To determine, using standard solutions, the main characteristicsof the analytical method used before performing sample testsPerform the sample screening (See Clause 6)Aim: To evaluate the quantity of analyte of interest in theanalysed sampleAre the validationcriteria in agreement with the method purpose ?Is the analyte detected with a S/N LoQ ?Adapt or modify the analytical method usedNOYESNO YESPerform sample assay using spike recovery (See 7.2)Aim: To
