EN 14185-2:2006

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Fettarme Lebensmittel - Bestimmung von N-Methylcarbamatrückständen - Teil 2: HPLC-Verfahren mit Reinigung auf einer Kieselgur-SäuleAliments non gras - Dosage des N-méthylcarbamates - Partie 2 : Méthode CLHP avec purification sur colonne de terre de diatoméesNon fatty foods - Determination of N-methylcarbamate residues - Part 2: HPLC method with clean-up on a diatomaceous earth column67.050Splošne preskusne in analizne metode za živilske proizvodeGeneral methods of tests and analysis for food productsICS:Ta slovenski standard je istoveten z:EN 14185-2:2006SIST EN 14185-2:2006en01-september-2006SIST EN 14185-2:2006SLOVENSKI
STANDARD
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 14185-2May 2006ICS 65.060 English VersionNon fatty foods - Determination of N-methylcarbamate residues -Part 2: HPLC method with clean-up on a diatomaceous earthcolumnAliments non gras - Dosage des N-méthylcarbamates -Partie 2 : Méthode CLHP avec purification sur colonne deterre de diatoméesFettarme Lebensmittel - Bestimmung von N-Methylcarbamatrückständen - Teil2: HPLC-Verfahren mitReinigung auf einer Kieselgur-SäuleThis European Standard was approved by CEN on 20 April 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2006 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14185-2:2006: ESIST EN 14185-2:2006

Precision Data.13 Bibliography.17
The method has been validated by collaborative study for aldicarb, carbofuran, furathiocarb, methomyl, oxamyl, propoxur and thiodicarb parent compounds and for the metabolites aldicarb sulfoxide, aldicarb sulfone (aldoxycarb) and 3-hydroxy-carbofuran in tomatoes and oranges at levels between 0,04 mg/kg and 0,25 mg/kg. No collaborative data are available for the performance of the method in the determination of other significant compounds although it is known that the method is unsatisfactory for benfuracarb. 2 Principle The sample is homogenized with dichloromethane, the homogenate is filtered and the filtrate evaporated. For citrus fruits only, the sample is homogenized with acetonitrile, the filtrate is washed with n-hexane and evaporated. In both cases, the residue is dissolved in an aqueous sodium chloride solution. The solution is transferred to a diatomaceous earth column and the column is eluted with dichloromethane. The eluates are evaporated and the residue is dissolved in methanol. In this solution, the N-methylcarbamates are determined by reversed-phase high-performance liquid chromatography (HPLC) with post-column hydrolysis. The methylamine formed is allowed to react with o-phthaldialdehyde and 2-mercaptoethanol and the derivatives are detected with a fluorescence detector [2].
3 Reagents 3.1 General Unless otherwise specified, use reagents of recognized analytical grade, preferably for HPLC and pesticide residue analysis, and distilled water or water of equivalent purity. Label all standard containers with name and purity of the pesticides. For the full chemical names and structures, see ISO 1750. 3.2 Safety aspects
WARNING — The use of this standard may involve hazardous materials, operations and equipment. This standard does not purport to address all the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use.
3.3 Acetonitrile 3.4 n-Hexane 3.5 Acetonitrile, saturated with n-hexane
In a separating funnel, shake 400 ml of acetonitrile (3.3) with 40 ml of n-hexane (3.4) for 3 min and use the lower layer. SIST EN 14185-2:2006

3.11 Solid support material, Extrelut NT2) refill packs 3.12 o-Phthaldialdehyde 3.13 Tetraborate buffer solution, 38,1 g/l sodium tetraborate decahydrate in water 3.14 2-Mercaptoethanol 3.15 Mobile phase A Water, purified by a LC-grade water purification system. Prior to use, filter it with gentle suction through a membrane filter (4.13). 3.16 Mobile phase B Acetonitrile (3.3). Prior to use, filter it with gentle suction through a membrane filter (4.13).
1)
Due to environmental reasons, also ethyl acetate can be used, however, only the use of dichloromethane has been tested in the inter-laboratory study, and therefore, the applicability of ethyl acetate has to be proven in an appropriate manner. 2) Hydrolysis Reagent for Carbamate Pesticide Analysis CB 130 and Derivatization Reagent 2 are products supplied by Pickering Laboratories, Mountain View, California, USA. This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of the product named. Equivalent products may be used if they can be shown to lead to the same results. 3) Sodium hydroxide solution for HPCE, Extrelut NT and RP Select B are products supplied by E. Merck, Darmstadt, Germany. This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of the product named. Equivalent products may be used if they can be shown to lead to the same results. 4) Celite 545 is a product supplied by Celite Corp. (World Minerals Inc., Santa Barbara, CA, USA). This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of the product named. Equivalent products may be used if they can be shown to lead to the same results. SIST EN 14185-2:2006

3.20 Pesticide standard solutions
Prepare appropriate standard solutions by diluting suitable amounts of pesticide stock solutions (3.19) with methanol, e.g. to 1 µg/ml or to 0,1 µg/ml, if necessary. 4 Apparatus 4.1 General Glassware shall be thoroughly cleaned. Hot detergent solution may be used for cleaning, but afterwards the glassware shall be well rinsed with distilled water and acetone before drying. Usual laboratory apparatus is used and, in particular, the following.
4.2 Food chopper 4.3 Homogenizer or high speed blender 4.4 Glass bottle, 500 ml 4.5 Rotary evaporator with a water bath, capable of being maintained at 35 °C
4.6 Buchner porcelain funnel, 9,5 cm diameter 4.7 Filtration flask, 1 l 4.8 Glass fibre filter, 9 cm diameter
4.9 Separating funnel, 1 l SIST EN 14185-2:2006

or Chromabond XTR (70 ml) 6). Used Extrelut NT 20 columns may be refilled with Extrelut NT refill packs (3.11). 4.11 High performance liquid chromatograph, equipped with
4.11.1
Binary pumping system with six-port injection valve with a 20 µl sample loop, a fluorescence detector and a quantification unit with an integrating system. 4.11.2
HPLC analytical column, stainless steel cartridge, 250 mm long, 4,0 mm inner diameter (e.g. packed with RP Select B 2) (see page 5)) (particle size 5 µm). 4.11.3
Post-column system, consisting of two reaction coils in different thermostats, two low-dead volume T-pieces, and two pulse-free reagent pumps. NOTE A complete post-column LC-system for the analysis of N-methylcarbamates is commercially available.
4.12 Ultrasonic bath 4.13 Membrane filter, pore size 0,45 µm 5 Sampling Prepare the laboratory sample according to a generally recommended method of sampling to achieve a representative part of the product to be analyzed. 6 Preparation of the samples Where possible, carry out the analysis of samples immediately on their arrival in the laboratory. Do not analyse a laboratory sample which is wholly or extensively spoiled. For analysis take only the portion of the laboratory sample to which the maximum residue level applies. No further plant-parts may be removed. A record of the plant-parts which have been removed shall be kept. The sample thus prepared is the test sample. If the sample cannot be analysed immediately, store it at 0 °C to 5 °C for no longer than 3 days before analysis. The reduction of the test sample shall be carried out in such a way that representative portions are obtained (e.g. by division into four and selection of opposite quadrants). When the samples are in small units (e.g. small fruits, legumes, cereals), the test sample shall be thoroughly mixed before weighing out the test portion. When the samples are in larger units, take wedge-shaped sections (e.g. large fruits and vegetables) or cross sections (e.g. cucumbers) which include the outer surface from each unit.
5) Chem Elut 20 ml
is a product supplied by Varian Inc., Palo Alto, CA, USA. This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of the product named. Equivalent products may be used if they can be shown to lead to the same results. 6) Chromabond XTR
is a product supplied by Macherey-Nagel, Düren, Germany. This information is given for the convenience of users of this European Standard and does not constitute
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