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1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 1528-3 : 1997 The E
2、uropean Standard EN 1528-3 : 1996 has the status of a British Standard ICS 67.040 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Fatty food Determination of pesticides and polychlorinated biphenyls (PCBs) Part 3. Clean-up methods Licensed Copy: sheffieldun sheffieldun, na, Fr
3、i Nov 17 08:44:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 1528-3 : 1997 This British Standard, having been prepared under the direction of the Consumer Products and Services Sector Board, was published under the authority of the Standards Board and comes into effect on 15 June 1997 BSI 1997
4、 The following BSI references relate to the work on this standard: Committee reference AW/-/3 Draft for comment 94/505376 DC ISBN 0 580 27381 4 Amendments issued since publication Amd. No.DateText affected Committees responsible for this British Standard The preparation of this British Standard was
5、entrusted to Technical Panel AW/-/3, Food analysis Horizontal methods, upon which the following bodies were represented: Association of Public Analysts Department of Trade and Industry Food and Drink Federation Institute of Food Science and Technology Ministry of Agriculture Fisheries and Food (Labo
6、ratory of the Government Chemist) Royal Society of Chemistry Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 17 08:44:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 1528-3 : 1997 BSI 1997i Contents Page Committees responsibleInside front cover National forewordii Foreword2 Text of EN 1528-3
7、3 Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 17 08:44:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ii BSI 1997 BS EN 1528-3 : 1997 National foreword This British Standard has been prepared by Technical Panel AW/-/3 and is the English language version of EN 1528-3: 1996 Fatty food Determina
8、tion of pesticides and polychlorinated biphenyls (PCBs) Part 3 : Clean-up methods published by the European Committee for Standardization (CEN). EN 1528-3 was produced as a result of international discussions in which the United Kingdom took an active part. Cross-references Publication referred toCo
9、rresponding British Standard EN 1528-1 : 1996BS EN 1528-1 : 1997 Fatty food Determination of pesticides and polychlorinated biphenyls (PCBs) Part 1 : General EN 1528-2 : 1996BS EN 1528-2 : 1997 Fatty food Determination of pesticides and polychlorinated biphenyls (PCBs) Part 2 : Extraction of fat, pe
10、sticides and PCBs, and determination of fat content EN 1528-4 : 1996BS EN 1528-4 : 1997 Fatty food Determination of pesticides and polychlorinated biphenyls (PCBs) Part 4 : Determination, confirmatory tests, miscellaneous Compliance with a British Standard does not of itself confer immunity from leg
11、al obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages 2 to 16, an inside back cover and a back cover. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 17 08:44:02 GMT+00:00 2006, Uncontrolled Copy, (c) BSI CEN Europ
12、ean Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1996 Copyright reserved to CEN members Ref. No. EN 1528-3 : 1996 E EUROPEAN STANDARDEN 1528-3 NORME EUROPE ENNE EUROPA ISCHE NORM November 1
13、996 ICS 67.040 Descriptors: Foodproducts,ediblefats,chemicalanalysis,determinationofcontent,pesticides,polychlorobiphenyl,purity, chromatography English version Fatty food Determination of pesticides and polychlorinated biphenyls (PCBs) Part3: Clean-up methods Aliments gras Dosage des pesticides et
14、des polychlorobiphe nyles (PCB) Partie 3 : Me thodes de purification Fettreiche Lebensmittel Bestimmung von pestiziden und polychlorierten Biphenylen (PCB) Teil 3 : Reinigungsverfahren This European Standard was approved by CEN on 1996-10-27. CEN members are bound to comply with the CEN/CENELEC Inte
15、rnal 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 Central Secretariat or to any CEN membe
16、r. 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 Central Secretariat has the same status as the official versions. CEN members
17、are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 17 08:44:02 GMT+00:00 2006, Uncontr
18、olled Copy, (c) BSI Page 2 EN 1528-3 : 1996 BSI 1997 Foreword This European Standard has been prepared by Technical Committee CEN/TC 275, Food analysis, horizontal methods, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by pub
19、lication of an identical text or by endorsement, at the latest by May 1997, and conflicting national standards shall be withdrawn at the latest by May 1997. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this
20、European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. This European Standard consists of the following Parts. Part 1 General presents the scope of the stan
21、dard and describes general considerations with regard to reagents, apparatus, gas chromatography etc., applying to each of the analytical methods selected. Part 2 Extraction of fat, pesticides and PCBs, and determination of fat content presents a range of analytical procedures for extracting the fat
22、 portion containing the pesticide and PCB residues from different groups of fat-containing foodstuffs. Part 3 Clean-up methods presents the details of methods A to H for the clean-up of fats and oils or the isolated fat portion, respectively, using techniques such as liquidliquid partition, adsorpti
23、on or gel permeation column chromatography. Part 4 Determination, confirmatory tests, miscellaneous gives guidance on some recommended techniques for the determination of pesticides and PCBs in fatty foodstuffs and on confirmatory tests, and lists a clean-up procedure for the removal of the bulk of
24、lipids when analysing large quantities of fat. Contents Page Foreword2 Introduction3 1Scope3 2Normative references3 3Principle3 4General3 5Method A: Liquidliquid partitioning with acetonitrile and clean-up on a Florisilcolumn (AOAC) 14 6Method B: Liquidliquid partitioning with dimethylformamide and
25、clean-up on a Florisilcolumn (Specht) 25 7Method C: Column chromatography on activated Florisil(AOAC) 37 8Method D: Column chromatography on partially deactivated Florisil (Stijve) 48 9Method E: Column chromatography on partially deactivated aluminium oxide (Greve column packing 60 g BioBeads S-X3re
26、sin4), pre-swelled overnight in the eluting mixture, approximately 48 cm bed length. 10.4.2 Rotary evaporator, with evaporation flasks of capacity 500 ml and a water bath capable of being controlled between 20 C and 50 C. 10.5 Procedure 10.5.1 Extraction of fat and pesticides 10.5.1.1 General Genera
27、l methods shall be carried out in accordance with EN 1528-2 : 1996. 10.5.1.2 Special method Place an approximately 40 g fat sample in a glass funnel (8 cm diameter) containing a glass wool plug. Place the funnel in a 250 ml beaker on a hot plate at 110 C maximum until the fat ceases to drip. Mix tho
28、roughly. 10.5.2 Clean-up by GPC When using a new GPC column, adjust the flow rate of the eluting mixture to 5 ml/min and check the calibration for quantitative recovery with 2,0 g of corn oil fortified with relevant compounds. Determine the appropriate dump and collect times for the desired residues
29、. Weigh about 2 g, to the nearest 10 mg, of liquid fat sample into a 10 ml volumetric flask, dilute to the mark with eluting mixture and mix thoroughly. Centrifuge or filter if particulate matter is visible. Load the 5 ml sample loop using approximately 7 ml of the solution. Elute the GPC column wit
30、h the eluting mixture, using the dump/collect times determined beforehand, at a flow rate of 5 ml/min. Collect the eluate in a 250 ml round-bottomed flask and rotary-evaporate just to dryness at a 30 C maximum bath temperature. Transfer the residue remaining after evaporation with small aliquot port
31、ions of iso-octane to a volumetric flask or a graduated test tube, and adjust the solution to a suitable volume, e.g. 5 ml, with iso-octane. 10.6 Determination Determination shall be carried out in accordance with clause 7 of EN 1528-1 : 1996 and clause 4 of EN 1528-4 : 1996. 10.7 Evaluation of resu
32、lts The results shall be evaluated in accordance with clauses 9 to 11 of EN 1528-1 : 1996. 10.8 Test report The results of the tests shall be reported in accordance with clause 12 of EN 1528-1 : 1996. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 17 08:44:02 GMT+00:00 2006, Uncontrolled Copy,
33、(c) BSI Page 12 EN 1528-3 : 1996 BSI 1997 11 Method G. Gel permeation chromatography (GPC) and column chromatography on partially deactivated silica gel (Specht) 7 11.1 Applicability This method has been shown to be applicable for the determination of 24 organochlorine pesticides and metabolites, th
34、e PCB indicator congeners and 13 organophosphorus pesticides, as given in annex A of EN 1528-1 : 1996. GPC is a very effective technique for separating the residues to be analysed from the surplus of lipids. It covers a particular broad range of compounds. For this reason, the GPC eluate will also c
35、ontain other pesticides and contaminants than those mentioned above, e.g. the pyrethroids and chlorinated benzenes or phenols. Moreover, GPC can be readily automated. A silica gel mini-column may be used to provide an additional clean-up and a fractionation of the residues according to their polarit
36、y, thus yielding extra information for identification. 11.2 Principle Extraction of the residues, together with the fat, from the sample by one of the procedures described in EN 1528-2 : 1996. Concentration of the extract almost to dryness, redissolving it in cyclohexane/ethyl acetate. Chromatograph
37、y using a gel permeation column, with cyclohexane/ethyl acetate as the eluting solvent. Concentration of the eluate almost to dryness, and redissolving it in n-hexane. Chromatography on a small column of partially deactivated silica gel, using eluants of increasing polarity. Concentration of the elu
38、ates for examination by GC. 11.3 Reagents and materials All reagents and materials used shall be suitable for the analysis of residues of pesticides and PCBs and shall be in accordance with clause 4 of EN 1528-1 : 1996. If purification is necessary, the procedures given in annex A are appropriate. 1
39、1.3.1 Cyclohexane. 11.3.2 Ethyl acetate. 11.3.3 GPC eluting mixture, cyclohexane (11.3.1) and ethyl acetate (11.3.2) 1 : 1 (V/V). 11.3.4 Acetone. 11.3.5 Iso-octane. 11.3.6 n-hexane. 11.3.7 Toluene. 11.3.8 Eluant 1, n-hexane (11.3.6) and toluene (11.3.7) 65 : 35 (V/V). 11.3.9 Eluant 2, toluene (11.3.
40、7). 11.3.10 Eluant 3, toluene (11.3.7) and acetone (11.3.4) 95 : 5 (V/V). 11.3.11 Sodium sulfate, granular, anhydrous, heated at 550 C for at least 2 h. 11.3.12 Silica gel, deactivated with 1,5 % water. Heat silica gel 60 (63 mm to 200 mm70 mesh= to 230 mesh), at 130 C for at least 5 h, allow to coo
41、l in a desiccator, and store in a tightly stoppered container in the desiccator. To 98,5 g dried silica gel in a 300 ml Erlenmeyer flask with a ground joint, add 1,5 ml water dropwise from a burette, with continuous swirling. Immediately stopper the flask with a ground stopper and shake vigorously f
42、or 5 min until all lumps have disappeared. Next shake for 2 h on a mechanical shaker, and then store in a tightly stoppered container. 11.4 Apparatus Usual laboratory apparatus and, in particular, the following. 11.4.1 Automated instrument for GPC, e.g. GPC Autoprep1001 or 1002, equipped with chroma
43、tographic column, 25 mm i.d., 40 cm long, and 23 5 ml sample loops; column packing approximately 50 g BioBeadsS-X3 resin, (38 mm up to 75 mm200 mesh to 400 mesh), preswelled= overnight in the GPC eluting mixture, approximately 32 cm bed length. 11.4.2 Rotary evaporator, with evaporation flasks of ca
44、pacity 500 ml and a water bath capable of being controlled between 20 C and 50 C. 11.4.3 Chromatographic tube, 7 mm i.d., 23 cm long, with extended outlet. 11.5 Procedure 11.5.1 Extraction of fat, pesticides and PCBs General methods shall be carried out in accordance with EN 1528-2 : 1996. 11.5.2 Ge
45、l permeation chromatography When using a new GPC column, adjust the flow rate of the eluting mixture to 5 ml/min and check the calibration with relevant compounds. Determine the appropriate dump and collect times for the desired residues. Dissolve up to 5 g of the fat or oil or of the extracted fat
46、portion in the GPC eluting mixture (11.3.3) in a volumetric flask. Dilute to the mark with the same mixture and mix thoroughly. Load the 5 ml sample loop using approximately 7 ml of the solution. Elute the GPC column with the GPC eluting mixture, using the dump/collect times determined beforehand, a
47、t a flow rate of 5 ml/min. Collect the eluate in a 250 ml round-bottomed flask and rotary-evaporate it to approximately 1 ml (rotate slowly, and immerse flask only slightly), transfer the concentrate to a ground-stoppered graduated test tube, rinse with ethyl acetate, and dilute to a suitable volume
48、, e.g. 5,0 ml, with ethyl acetate. NOTE. For the analysis of organophosphorus pesticides, the GPC eluate can be directly injected for gas chromatographic examination, if a phosphorus selective detector is used. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 17 08:44:02 GMT+00:00 2006, Uncontrol
49、led Copy, (c) BSI Page 13 EN 1528-3 : 1996 BSI 1997 11.5.3 Silica gel mini column chromatography Pipette 2,5 ml of the solution derived from 11.5.2 into a round-bottomed flask with a ground joint, and add 5 ml of iso-octane (11.3.5). Carefully evaporate to 1 ml (on no account to dryness) in a rotary evaporator (rotate slowly and immerse flask only slightly). If the solution still smells of ethyl acetate, again add iso-octane and repeat the evaporation. Pack the chromatographic tube (11.4.3) in the following ord
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