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STANDARDSIST EN 12821:20001DGRPHãþD
SIST EN 12821:2009
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 12821April 2009ICS 67.050Supersedes EN 12821:2000
English VersionFoodstuffs - Determination of vitamin D by high performanceliquid chromatography - Measurement of cholecalciferol (D3) orergocalciferol (D2)Produits alimentaires - Dosage de la vitamine D parchromatographie liquide haute performance - Dosage ducholécalciférol (D3) et de l' ergocalciférol (D2)Lebensmittel - Bestimmung von Vitamin D mitHochleistungs-Flüssigchromatographie - Bestimmung vonCholecalciferol (D3) oder Ergocalciferol (D2)This European Standard was approved by CEN on 21 February 2009.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 CEN 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 translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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:
Avenue Marnix 17,
B-1000 Brussels© 2009 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 12821:2009: ESIST EN 12821:2009
EN 12821:2009 (E) 2 Contents Page Foreword .3 1 Scope .4 2 Normative references .4 3 Principle .4 4 Reagents .4 5 Apparatus .8 6 Procedure .9 7 Calculation . 11 8 Precision . 12 9 Test report . 13 Annex A (informative)
Examples of suitable HPLC systems . 14 Annex B (informative)
Examples of suitable extraction and saponification conditions . 15 Annex C (normative)
Examples of suitable semi-preparative and analytical HPLC chromatograms . 16 Annex D (informative)
Precision data . 18 Annex E (informative)
Additional cleanup step for the determination of vitamin D with use of preparative TLC, column chromatography and or SPE . 20 Bibliography . 24
SIST EN 12821:2009
EN 12821:2009 (E) 3 Foreword This document (EN 12821:2009) 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 publication of an identical text or by endorsement, at the latest by October 2009, and conflicting national standards shall be withdrawn at the latest by October 2009. Attention 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 12821:2000. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, 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 the United Kingdom.
SIST EN 12821:2009
EN 12821:2009 (E) 4 1 Scope This European Standard specifies a method for the determination of vitamin D3 (cholecalciferol) or vitamin D2 (ergocalciferol) in foodstuffs by high performance liquid chromatography (HPLC). Vitamin D3 is primary in foodstuffs of animal origin, while vitamin D2 is primary in wild mushrooms. Both vitamin D3 and vitamin D2 can be present in fortified foodstuffs. This European Standard is not applicable for samples with a content of vitamin D3 and vitamin D2. Apart from the vitamin D activity from the parent forms, vitamin D3 and vitamin D2, the corresponding metabolites 25-hydroxy vitamin D and 1,25-dihydroxy vitamin D also contribute to the vitamin D activity. This European Standard does only include measurement of vitamin D3 or vitamin D2. This European Standard provides the base for the analytical methods. It is intended to serve as a frame in which the analyst can define his own analytical work in accordance to the standard procedure. This method has been validated in inter-laboratory tests on fortified and non-fortified samples such as margarine, milk, milk powder, liquid infant formula, infant formula, cooking oil, and fish oil at levels from 0,4 µg/100 g to 14 µg/100 g. Further information on the validation data is given in Annex D. 2 Normative references The following referenced documents are 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. EN ISO 3696, Water for analytical laboratory use - Specification and test methods (ISO 3696:1987). 3 Principle Vitamin D3 and vitamin D2 are saponified in the foodstuffs using alcoholic potassium hydroxide solution and extracted by an appropriate solvent. The determination of vitamin D3 or vitamin D2 in an appropriate sample extract solution is carried out by semi-preparative normal phase HPLC followed by reverse-phase analytical HPLC. If vitamin D3 is to be determined, then vitamin D2 is used as an internal standard. If vitamin D2 is to be determined, then vitamin D3 is used as an internal standard. Vitamin D is detected by ultraviolet (UV) spectrometry and peaks are identified on the basis of retention times and additionally by UV spectral profile if diode-array detection is used. The determination is carried out by the internal standard procedure using peak areas or peak heights, see [1] to [8]. 4 Reagents 4.1 General During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and water of at least grade 1 according to EN ISO 3696. SIST EN 12821:2009
EN 12821:2009 (E) 5 4.2 Methanol 4.3 Ethanol, volume fraction 3(C2H5OH) = 100 %. 4.4 Ethanol, 3(C2H5OH) = 96 %. 4.5 Sodium sulfate, anhydrous. 4.6 KOH solutions for saponification, in suitable concentrations, e.g. mass concentration (KOH) = 50 g/100 ml or (KOH) = 60 g/100 ml, or alcoholic solutions, e.g. 28 g of KOH in 100 ml of an ethanol and water mixture with a volume fraction of ethanol of 90 %. 4.7 Antioxidants, such as ascorbic acid (AA), sodium ascorbate, pyrogallol, sodium sulfide (Na2S) or butylated hydroxytoluene (BHT). 4.8 Solvents and extraction solvents, such as diethyl ether (peroxide-free), dichloromethane, light petroleum, n-hexane, ethylacetate or appropriate mixtures thereof. 4.9 HPLC Mobile phases 4.9.1 Examples of solvent mixtures for normal phase semi-preparative HPLC Examples of appropriate solvent mixtures (given as volume fractions) for normal phase semi-preparative HPLC include: n-hexane and 2-propanol (98 + 2), (99 + 1) or (95 + 5); n-hexane and isoamyl alcohol (99 + 1); n-hexane, 2-propanol and tetrahydrofuran (98 + 1 + 1); iso-octane and iso-butanol (99 + 1); n-heptane and 2-propanol (97 + 3).
4.9.2 Examples of solvent and solvent mixtures for reverse-phase analytical HPLC Examples of appropriate solvent and solvent mixtures (given as volume fractions) for reverse-phase analytical HPLC include: methanol; methanol and water (95 + 5) or (93 + 7); acetonitrile and methanol (80 + 20), (90 + 10) or (70 + 30); acetonitrile, chloroform and methanol (93 + 4 + 3).
SIST EN 12821:2009
EN 12821:2009 (E) 6 4.10 Standard substances 4.10.1 Ergocalciferol standard substance (vitamin D2), M(C28H44O) = 396,7 g/mol Vitamin D2 standard substance shall be of the highest purity obtainable (having a mass fraction of greater than 98 %) and shall be stored according to the supplier's instructions (in the absence of light, typically less than 4 °C). 4.10.2 Cholecalciferol standard substance (vitamin D3), M(C27H44O) = 384,6 g/mol Vitamin D3 standard substance shall be of the highest purity obtainable (having a mass fraction of greater than 98 %) and shall be stored according to the supplier's instructions (in the absence of light, typically less than 4 °C). 4.11 Stock solutions 4.11.1 Vitamin D2 stock solution Weigh about 100 mg of vitamin D2 (4.10.1) to the nearest milligram into a one mark 100 ml volumetric flask, dissolve in ethanol (4.4) and dilute to the mark with ethanol. This solution contains approximately 1 mg/ml of vitamin D2. Store below 4 °C and protect from light. Calculate the mass concentration of the stock solution and the mass fraction of the vitamin D2 standard by the procedure described in 4.12.1. This solution is stable for 6 months at - 18 °C. 4.11.2 Vitamin D3 stock solution Weigh about 100 mg of vitamin D3 (4.10.2) to the nearest milligram into a one mark 100 ml volumetric flask, dissolve in ethanol (4.4) and dilute to the mark with ethanol. This solution contains approximately 1 mg/ml of vitamin D3. Store below 4 °C and protect from light. Calculate the mass concentration of the stock solution and the mass fraction of the vitamin D3 standard by the procedure described in 4.12.2. This solution is stable for 6 months at - 18 °C. 4.12 Standard solutions 4.12.1 Vitamin D2 standard solution Pipette 1 ml of the vitamin D2 stock solution (4.11.1) into a one mark 100 ml volumetric flask and dilute to the mark with ethanol (4.4). This solution contains approximately 10 µg/ml of vitamin D2. Prepare this solution on the day of use. NOTE The mass concentration of the standard solution can be adjusted if necessary to suit the analytical requirements. Measure the absorption of the vitamin D2 standard solution in a 1 cm quartz cell at a wavelength of 265 nm using ethanol in the reference path. Calculate the mass concentration of vitamin D2, D2, in microgram per millilitre of the standard solution using Equation (1): bMA×××=ερ1000D2265D2 (1) SIST EN 12821:2009
EN 12821:2009 (E) 7 where: A265 is the absorption of the vitamin D2 standard solution at 265 nm; MD2 is the molar mass of vitamin D2 (MD2 = 396,7 g/mol); 0 is the molar absorption coefficient of vitamin D2 (here: 0
= 18 843
m2/mol, calculated from the % 1cm 1E value, see [9]); b is the optical path length of the quartz cell in centimetres. 4.12.2 Vitamin D3 standard solution Pipette 1 ml of the vitamin D3 stock solution (4.11.2) into a one mark 100 ml volumetric flask and dilute to the mark with ethanol (4.4). This solution contains approximately 10 µg/ml of vitamin D3. Prepare this solution on the day of use. NOTE The mass concentration of the standard solution can be adjusted if necessary to suit the analytical requirements. Measure the absorption of the vitamin D3 standard solution in a 1 cm quartz cell at a wavelength of 265 nm using ethanol (4.4) in the reference path. Calculate the mass concentration of vitamin D3, D3, in microgram per millilitre of the standard solution using Equation (2): bMA×××=ερ1000D3265D3 (2) where: A265 is the absorption of the vitamin D3 standard solution at 265 nm; MD3 is the molar mass of vitamin D3 (MD3 = 384,6 g/mol); 0 is the molar absorption coefficient of vitamin D3 (here: 0
= 18 461
m2/mol, calculated from the % 1cm 1E value, see [9]); b is the optical path length of the quartz cell in centimetres. 4.13 Internal standard solutions 4.13.1 Vitamin D2 internal standard solution Pipette 10 ml of the vitamin D2 standard solution (4.12.1) into a one mark 100 ml volumetric flask and dilute to the mark with ethanol (4.4). Prepare this solution on the day of use. 4.13.2 Vitamin D3 internal standard solution Pipette 10 ml of the vitamin D3 standard solution (4.12.2) into a one mark 100 ml volumetric flask and dilute to the mark with ethanol (4.4). Prepare this solution on the day of use. NOTE If vitamin D3 is to be determined, then vitamin D2 is used as an internal standard. If vitamin D2 is to be determined, then vitamin D3 is used as an internal standard. SIST EN 12821:2009
EN 12821:2009 (E) 8 4.14 Vitamin D2 and vitamin D3 semi-preparative standard solution Pipette 5 ml of the vitamin D2 standard solution (4.12.1) and 5 ml of the vitamin D3 standard solution (4.12.2) into a rotary evaporator flask and carefully remove the solvent (at not more than 40 °C). Re-dissolve the residue in 100 ml of the semi-preparative HPLC mobile phase (4.9.1). The concentration of the semi-preparative standard may be adjusted if necessary to suit the HPLC system in use (5.4 or 5.5). 4.15 Vitamin D2 and vitamin D3 analytical standard solution Pipette 5 ml of the vitamin D2 standard solution (4.12.1) and 5 ml of the vitamin D3 standard solution (4.12.2) into a rotary evaporator flask and carefully remove the solvent (at not more than 40 °C). Re-dissolve the residue in 50 ml of the analytical HPLC mobile phase (4.9.2). 5 Apparatus 5.1 General Usual laboratory apparatus and, in particular, the following. 5.2 UV spectrometer, capable of measuring at a wavelength of 265 nm. 5.3 Rotary evaporator, with water bath and vacuum unit NOTE The use of nitrogen is recommended for releasing the vacuum. 5.4 Semi-preparative HPLC system, consisting of a pump, sample injection device, UV detector, a means of collecting a defined aliquot portion of column eluent, and a recorder or integrator. 5.5 Analytical HPLC system, consisting of a pump, sample injection device, UV detector, recorder/integrator or similar data capture device. 5.6 HPLC columns 5.6.1 Semi-preparative normal phase column, e.g. silica or bonded cyano-amino, particle size 5 µm, diameter 4,0 mm to 8,0 mm, length 250 mm to 300 mm. See Annex A for more information. 5.6.2 Analytical reverse phase column, e.g. C18 reverse phase, particle size 5 µm, diameter 4,0 mm to 4,6 mm, length 250 mm. See Annex A for more information. 5.6.3 Packing materials Particle sizes and column dimensions other than those specified in this European Standard may be used, but the analyst has to ensure that they provide adequate separation of the vitamins D from matrix interferences if equivalent results are to be obtained. 5.7 Filter device Large and small scale filter devices to filter HPLC mobile phases and sample solutions respectively, e.g. of 0,45 µm pore size or similar is appropriate.
NOTE Filtering of the mobile phase as well as of the sample test solution through a membrane filter prior to use or injection usually increases longevity of the columns. SIST EN 12821:2009
EN 12821:2009 (E) 9 6 Procedure 6.1 General Vitamin D2 and vitamin D3 are sensitive to UV radiation and to oxidizing agents (e.g. atmospheric oxygen). It is therefore necessary to exclude UV light by using amber glassware, aluminium foil or UV absorbing materials. Antioxidants need to be added to solutions containing extracted vitamin, and nitrogen flushing should be used. The solvents shall be evaporated under reduced pressure using a rotary evaporator at not more than 40 ºC. 6.2 Preparation of the test sample Homogenize the test sample. Comminute coarse material thoroughly and homogenize in a food blender or liquidiser. Precautions such as pre-cooling the sample shall be taken to avoid exposure to high temperatures. After this preparation the test sample shall be analysed without delay. Protect samples from light.
6.3 Preparation of the sample test solution 6.3.1 Saponification Saponify 10 g to 30 g of the test sample by refluxing, preferably under nitrogen, using suitable amounts of ethanol (4.4), water, an antioxidant (4.7) such as ascorbic acid, sodium ascorbate or pyrogallol and one of the potassium hydroxide solutions (4.6). Add the antioxidants to the sample prior to the addition of potassium hydroxide. Sodium sulfide (4.7) may also be added to obviate the oxidative catalytic effects of traces of metals. If vitamin D3 is to be determined, pipette an appropriate amount of vitamin D2 internal standard solution (4.13.1) into the saponification flask. The amount of vitamin D2 internal standard solution added shall be similar to the amount of vitamin D3 expected in the sample. If vitamin D2 is to be determined then vitamin D3 standard solution (4.13.2) shall be added as the internal standard. A sample that does not contain the internal standard should be taken through the analytical procedure to ensure that there is no sample matrix interference at the internal standard retention time. Examples of suitable ratios of reagents are given in Table 1. Table 1 — Examples of suitable ratios of reagents Sample Ethanol Pyrogallol Ascorbic acid /
Na ascorbate Potassium hydroxide 10 g to 30 g 100 ml 0,5 g to 1 g 1,0 g to 2,5 g 50 ml of a 50 g/100 ml solution
The usual time of saponification ranges from 20 min to 45 min with temperatures of 70 °C to 100 °C. Saponification may also be carried out at room temperature overnight (approximately 16 h) under otherwise same conditions. If after saponification and cooling, fat or oil is present on the surface of the saponification mixture, additional ethanolic potassium hydroxide has to be added and saponification time extended. NOTE Conditions found suitable for saponification of a margarine and a milk powder are shown in Annex B. SIST EN 12821:2009
EN 12821:2009 (E) 10 6.3.2 Extraction In order to avoid emulsions, an amount of water has to be added to the saponified sample solution so that the ratio of alcohol to water in the resulting solution is 1:1. Extract the vitamins D2 and D3 from the cooled saponification mixture using a suitable solvent, or mixture of solvents (4.8), and repeat the procedure two to four times with volumes ranging from 100 ml to 200 ml. Wash the combined solvent extracts to neutral pH with water (typically 5 times with 50 ml to 100 ml). NOTE Some methods prescribe washing to neutrality with 3 % or 5 % potassium hydroxide in 0,9 % sodium chloride solution buffered in 2,6 mol/l sodium acetate (pH = 7), or similar mixtures. Annex B shows extraction conditions found suitable for a margarine and a milk powder. 6.3.3 Concentration Evaporate sample extracts using a rotary evaporator (5.3) under reduced pressure, and at a temperature not exceeding 40 °C. Prior to evaporation it is good practice to add an antioxidant (e.g. 2 ml of 1 mg/ml BHT in n-hexane) to the sample extract. Absolute ethanol (4.3) or anhydrous sodium sulfate (4.5) should be added to the concentrated sample extract to assist in the removal of traces of water (azeotropic distillation). At this stage in the analytical procedure, additional cleanup of the sample extract may be employed to remove potential interferences. If additional cleanup is employed, the procedure shall be fully validated for use. NOTE Annex E outlines three different additional cleanup steps. The cleanup step with use of column chromatography (E.2) and with use of SPE (E.3) should always be combined, and have shown to be useful for foods, for example margarine and oil. The cleanup step with use of preparative TLC (E.1) is preferable for feed and supplements like tablets or capsules. For supplements it may be combined with E.3 if necessary. 6.3.4 Dilution Re-dissolve the residue in a small, known volume of solvent which is compatible with the semi-preparative HPLC system. Addition of a small amount of anhydrous sodium sulfate will remove residual traces of water. 6.4 Calibration Use standard solutions of vitamin D2 (4.12.1) and vitamin D3 (4.12.2) to calibrate the semi-preparative (5.6.1) and analytical HPLC (5.6.2) systems and assess system suitability. 6.5
HPLC system suitability Chromatograph a mixed vitamin D2 and D3 semi-preparative standard (4.14) on the semi-preparative HPLC system (5.6.1) until a single vitamin D peak is eluted with a reproducible retention time. Once achieved, this will allow precise band-cut collection of the vitamin D fraction from sample extracts. The chromatographic conditions of the semi-preparative HPLC have to be adjusted to achieve optimal separation of vitamin D from tocopherols and other food matrix interferences. See Annex C for example chromatograms. Chromatograph a mixed vitamin D2 and D3 analytical standard solution (4.15) on the analytical HPLC system and adjust the chromatographic conditions until the resolution of vitamin D2 from vitamin D3 is at least 98 % complete (i.e. the resolution factor shall be greater than 1,0), and the vitamins are resolved from all food matrix interferences. SIST EN 12821:2009
EN 12821:2009 (E) 11 6.6 Determination 6.6.1 Semi-preparative HPLC Inject an aliquot portion of the concentrated sample extract onto the semi-preparative HPLC system (5.6.1) and collect the vitamin D fraction via a band-cut. The time window for band-cut collection shall have been previously determined using a vitamin D standard (6.5). The band-cut shall be sufficiently wide to collect all of the vitamin D band but sufficiently narrow to reduce the possibility of collecting tocopherols or other interfering compounds.
A typical semi-preparative chromatogram is shown in Annex C. 6.6.2 Analytical HPLC Evaporate the band-cut from the semi-preparative HPLC to dryness and re-dissolve in solvent compatible with the analytical HPLC mobile phase. Inject aliquot portions of the sample extract onto the analytical HPLC system and identify the vitamin D2 and D3 peaks (6.6.3). The vitamin D2 and D3 peaks shall be resolved from sample matrix interferences. A typical analytical HPLC chromatogram is shown in Annex C. 6.6.3 Identification Identify vitamins D2 and D3 by comparing retention times from sample chromatograms with those obtained from standards under the same chromatographic conditions (6.5). The use of diode array detection allows the UV profile of the vitamin D peaks to be scrutinised and peak purity assessed. Re-chromatographing sample extracts using different UV detector wavelengths may also be used to assess vitamin D peak purity and confirm peak identity. 6.6.4 Number of determinations Perform at least two independent determinations. 6.7 Internal standard procedure and response factor Calculate the response factor of vitamin D3 to D2, Rf, by internal standard procedure using standards of known concentration (4.13) using Equation (3): STD3STD2STD2STD3fρρ××=AAR (3)
where: ASTD3 is the peak area or height for the vitamin D3 standard solution; ASTD2 is the peak area or height for the vitamin D2 standard solution; STD2 is the mass concentration of vitamin D2 in the standard solution, in microgram per millilitre; STD3 is the mass concentration of vitamin D3 in the standard solution in microgram per millilitre. 7 Calculation Calculate the mass fraction, wD3, of vitamin D3 in µg/100 g, using Equation (4):
SIST EN 12821:2009
EN 12821:2009 (E) 12 mRAIAw××××=fSD2SSD3D3100 (4)
where: IS is the mass of the internal standard of vitamin D2, in the test portion, in microgram; m is the mass of the sample taken for the saponification, in grams; Rf see Equation (3); ASD3 is the peak area or height for vitamin D3 in the sample solution; ASD2 is the peak area or height for vitamin D2 in the sample solution. 8 Precision 8.1 Statistical summary The precision data of different HPLC methods for the determination of vitamin D3 were established in 1994 by an international comparison study organized on behalf of the European Commission's Standards Measurement and Testing Programme on a sample of margarine (Certified Reference Material (CRM 122)) and milk powder (CRM 421) and provided the statistical information shown in Annex D. The precision data on porridge and milk powder were established in an interlaboratory test on a method using a calculation based on external standard, in accordance with ISO 5725:1986. See Annex D. The precision data on milk, liquid infant formula, cooking oil, margarine, infant formula and fish oil were established in an interlaboratory test in accordance with the AOAC Guidelines for collaborative study procedures to validate characteristics of a method of analysis, see Annex D. The data derived from these comparison studies may not be applicable to analyte concentration ranges and sample matrices other than those given in Annex D. 8.2 Repeatability The absolute difference between two single test results found on identical test material by one operator using the same apparatus within the shortest feasible time interval will exceed the repeatability limit r in not more than 5 % of the cases. The values are: Margarine: x = 12,3 µg/100 g r = 2,32 µg/100 g Milk powder: x = 14,3 µg/100 g r = 2,09 µg/100 g
Milk: x = 0,418 µg/100 g r = 0,054 µg/100 g Liquid infant formula: x = 1,38 µg/100 g r = 0,23 µg/100 g Cooking oil: x = 4,61 µg/100 g r = 0,96 µg/100 g Margarine: x = 8,39 µg/100 g r = 1,52 µg/100 g Infant formula: x = 10,1 µg/100 g r = 0,7 µg/100 g Fish oil: x = 11,6 µg/100 g r = 0,7 µg/100 g
8.3 Reproducibility The absolute difference between two single test results found on identical test material reported by two laboratories will exceed the reproducibility limit R in not more than 5 % of the cases. SIST EN 12821:2009
EN 12821:2009 (E) 13 The values are: Margarine: x= 12,3 µg/100 g R = 2,66 µg/100 g Milk powder: x = 14,3 µg/100 g R = 2,21 µg/100 g Milk: x = 0,418 µg/100 g R = 0,106 µg/100 g Liquid infant formula: x = 1,38 µg/100 g R = 0,47 µg/100 g Cooking oil: x = 4,61 µg/100 g R = 3,11 µg/100 g Margarine: x = 8,39 µg/100 g R = 1,60 µg/100 g Infant formula: x = 10,1 µg/100 g R = 2,0 µg/100 g Fish oil: x = 11,6 µg/100 g R = 5,8 µg/100 g 9 Test report The test report shall contain at least the following data: a) all information necessary for the identification of the sample; b) a reference to this European Standard or to the method used; c) the results and the units in which the results have been expressed; d) the date and type of sampling procedure (if known); e) the date of receipt; f) the date of test; g) any particular points observed in the course of the test; h) any observations not specified in the method or regarded as optional which might have affected the results. SIST EN 12821:2009
EN 12821:2009 (E) 14 Annex A (informative)
Examples of suitable HPLC systems Table A.1 — Examples of semi-preparative HPLC systems used for sample test solution cleanup by participants in the EU MAT certification study for vitamin D [8] Column Dimensions, mm Mobile phase, (V + V)Detector,
Polygosil 60, 5 µm 250 x 8 iso-octane + iso-butanol (99 + 1) 265 nm LiChrospher Si 60, 5 µm 250 x 4 n-hexane + 2-propanol (99 + 1) 265 nm LiChrospher Si 100, 5 µm 250 x 8 n-hexane + 2-propanol (98 + 2) 265 nm µ Porasil silica 300 x 3,9 n-hexane + THF + 2-propanol (98 + 1 + 1) 265 nm Partisil PAC, 5 µm 250 x 4,6 n-hexane + isoamylalcohol (99 + 1) 265 nm LiChrosorb Si 60 250 x 4 n-hexane + 2-propanol + THF (98 + 1 + 1) 265 nm LiChrosorb Si 60 250 x 4 n-hexane +
...