1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 11986:2010Ophthalmic optics Contactlenses and contact lens careproducts Determinationof preservative uptake andrelease (ISO 11986:2010)BS EN ISO 11986:2010 BRITISH STAN
2、DARDNational forewordThis British Standard is the UK implementation of EN ISO11986:2010. It supersedes BS EN ISO 11986:2001 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee CH/172/9, Contact lenses and contact lens care products.A list of organizations r
3、epresented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2010ISBN 978 0 580 65522 7ICS 11.040.70Compliance with a British Standard cannot confe
4、r immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 December 2010.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 11986 November 2010 ICS 11.040.70 S
5、upersedes EN ISO 11986:2000English Version Ophthalmic optics - Contact lenses and contact lens care products - Determination of preservative uptake and release (ISO 11986:2010) Optique ophtalmique - Lentilles de contact et produits dentretien pour lentilles de contact - Dtermination de labsorption/a
6、dsorption et du relargage des conservateurs (ISO 11986:2010) Augenoptik - Kontaktlinsen und Kontaktlinsenpflegemittel - Bestimmung der Aufnahme und Wiederfreisetzung von Konservierungsmitteln (ISO 11986:2010) This European Standard was approved by CEN on 31 October 2010. CEN members are bound to com
7、ply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELE
8、C Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the s
9、ame status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
10、Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any m
11、eans reserved worldwide for CEN national Members. Ref. No. EN ISO 11986:2010: EBS EN ISO 11986:2010EN ISO 11986:2010 (E) 3 Foreword This document (EN ISO 11986:2010) has been prepared by Technical Committee ISO/TC 172 “Optics and photonics” in collaboration with Technical Committee CEN/TC 170 “Ophth
12、almic optics” the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2011, and conflicting national standards shall be withdrawn at the latest by May 2011. At
13、tention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 11986:2000. According to the CEN/CENELEC Internal Regula
14、tions, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malt
15、a, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 11986:2010 has been approved by CEN as a EN ISO 11986:2010 without any modification. BS EN ISO 11986:2010ISO 11986:2010(E) ISO 2010 All rights
16、reserved iiiForeword 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 f
17、or which 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
18、 all 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 a
19、re circulated 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
20、responsible for identifying any or all such patent rights. ISO 11986 was prepared by Technical Committee ISO/TC 172, Optics and photonics, Subcommittee SC 7, Ophthalmic optics and instruments. This second edition cancels and replaces the first edition (ISO 11986:1999), which has been technically rev
21、ised. BS EN ISO 11986:2010ISO 11986:2010(E) iv ISO 2010 All rights reservedIntroduction Contact lens care products are a complex mixture of organic and inorganic substances. For reasons of microbiological safety, contact lens disinfecting solutions, as well as care products in multi-use containers,
22、contain substances with antimicrobial activity. From many years of experience in contact lens wear, it is known that irritation and sensitization problems sometimes occur due to these preservatives being absorbed and released by the matrix of the contact lens. For these reasons, it is necessary to b
23、e able to estimate the extent of preservative uptake and release by contact lenses. The preservative uptake and release test provides a general method for measuring the uptake of preservatives in solution by contact lenses and the release of preservatives from contact lenses in an aqueous medium. Th
24、e analytical method to be used for quantification of specific preservatives is not indicated here. Chemical characteristics of the preservative, as well as concentration in the contact lens care product and degree of uptake by the contact lens, must be taken into consideration in selecting an approp
25、riate analytical method. Contact lens uptake and release data may be useful in characterizing the potential for a new or modified contact lens material to produce a toxic or irritating reaction in the eye from the uptake and binding or release of preservatives from currently marketed contact lens ca
26、re products. BS EN ISO 11986:2010INTERNATIONAL STANDARD ISO 11986:2010(E) ISO 2010 All rights reserved 1Ophthalmic optics Contact lenses and contact lens care products Determination of preservative uptake and release 1 Scope This International Standard provides general procedures for the selection o
27、f methods, preparation of samples, and conduct of testing for the uptake and release of preservatives from contact lenses. NOTE 1 Due to the manifest difficulties of reproducibility when coating contact lenses with mineral and organic deposits encountered during lens wear, these methods are only app
28、licable to new and unused contact lenses. NOTE 2 Preservative depletion by a contact lens in the limited volume of a lens case could compromise disinfection performance. This International Standard does not measure disinfection performance. 2 Normative references The following referenced documents a
29、re indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 18369-3:2006, Ophthalmic optics Contact lenses Part 3: Measurement methods 3 Prin
30、ciple The contact lenses to be tested are immersed in the test product at 25 C 2 C and the preservative content analysed at regular intervals of time until a steady-state condition has been achieved. After reaching the steady-state condition, each contact lens is immersed in 1 ml of saline solution
31、for contact lens testing, the saline solution prepared in accordance with ISO 18369-3:2006, 4.7, at 37 C 2 C. At discrete intervals up to and including 16 h, and at intervals until no additional release is observed, if required, the solution is analysed for the amount of preservative that has been e
32、xtracted at each time point. 4 Procedure 4.1 General The following information shall be obtained before commencing the estimation: a) evidence that the selected test method is suitable for the detection and estimation of the particular preservative; NOTE 1 Examples of methods suitable for analysing
33、some preservatives are presented in US FDA guidelines (see Reference 2). b) evidence that the test method has the required repeatability and reproducibility, and a detection limit suitable for the assay; BS EN ISO 11986:2010ISO 11986:2010(E) 2 ISO 2010 All rights reservedc) the number of determinati
34、ons required to satisfy b); NOTE 2 Multiple determinations might be necessary when the analysis result is close to the limit of detection and/or when the analysis method has a low precision. d) the criteria needed to confirm that equilibrium has been achieved in the extraction process; e) the amount
35、 of test solution taken will need to ensure that the quantity of absorbed preservative does not reduce the concentration of the preservative in the test solution to less than 25 % of the initial preservative concentration in the test solution; f) a sufficient number of contact lenses of each materia
36、l type shall be used to ensure that the quantity of absorbed and released preservative is higher than the detection limit of the method of analysis, and also ensure that enough lenses are available for preservative release measurement at each time point. 4.2 Uptake of preservatives from test product
37、 4.2.1 Select the appropriate contact lens care product and/or the appropriate contact lens material for testing. 4.2.1.1 To determine the preservative uptake of a new or modified contact lens material, select the appropriate contact lens care product based on the intended use of the contact lens ca
38、re product (e.g. recommended for use with hydrogel contact lenses, or rigid gas-permeable contact lenses). 4.2.1.2 To determine the uptake of a new or modified preservative in the contact lens care product, select the appropriate contact lens materials for testing from currently marketed contact len
39、ses based on the intended use of the contact lens care product (e.g. recommended for use with hydrogel contact lenses, or rigid gas-permeable contact lenses). The selection of test lenses and lens care products should be justified. For hydrogel lenses, representatives from low water and medium/high
40、water ionic and non-ionic lens groups and from silicone hydrogel lenses should be included. For rigid lenses, representative lenses from silicone, fluorine and silicon-fluorine lens groups should be included (see ISO 18369-1). 4.2.2 Determine the initial preservative level in the test solution. 4.2.
41、3 Record the volume of soak solution and immerse the test lenses in the test solution in a suitable closed container (see the following paragraph) at 25 C 2 C, and shake occasionally (to ensure adequate mixing of the solution surrounding the contact lens during the study). Take aliquot portions of t
42、he test solution at different time intervals and analyse each for its preservative content. During day 1, take aliquot portions at the proposed regimen time, at 8 h and at 24 h. Continue the procedure at intervals of not less than 24 h until the aliquot portions show that no more preservative has be
43、en absorbed, or the maximum recommended storage time for the lenses in the contact lens care products has been reached. Additional time points during the first day may be included to determine the uptake profile. It is preferable to use containers that have been demonstrated to absorb insignificant
44、amounts of the preservative. However, if the container does absorb the preservative, this should be allowed for when carrying out the test procedure. In this case, for example, an appropriate control solution should also be monitored to determine the amount of preservative absorbed by the container.
45、 NOTE 1 Alternatively, the amount of preservative taken up by the contact lens can be determined directly by methods that provide reproducible quantitative extraction from the contact lens, using a suitable solvent and measuring the amount of preservative found in the extraction solvent. If the aliq
46、uot portions taken are large enough to significantly alter the ratio between the volume of the test solution and the mass of the test lenses, additional test lenses and containers should be used for each sampling interval. NOTE 2 If the percentage of the preservative absorbed by the test lenses exce
47、eds 75 % of the available preservative, it might be necessary to repeat the test with an increased ratio of the test solution volume to number/mass of test lenses. BS EN ISO 11986:2010ISO 11986:2010(E) ISO 2010 All rights reserved 34.3 Release of preservatives from test lenses After reaching a stead
48、y-state condition (see 4.2.3), remove the test lenses from the test solution and remove any excess solution by gently touching each test lens with an absorbent tissue without using excessive force or contact time. Immerse the test lenses in saline solution, prepared in accordance with ISO 18369-3:20
49、06, 4.7, at a ratio of one lens per millilitre of saline solution, in a closed container. Leave the test lenses immersed at 37 C 2 C and shake occasionally. Take aliquot portions of the solvent at different times and analyse each for its preservative content. Measure aliquot portions of the solvent at 1 h, 2 h, 4 h and 16 h and until no additional release (steady state) is observed. NOTE If the aliquot portions taken are large enough to significantly alter the ratio between the test solution and the mass of the test lenses, use ad
