Multiple Mycotoxins Determination in Food by LC-MS/MS: An International Collaborative Study

An intercollaborative study was organized to evaluate the performance characteristics of a liquid chromatography tandem mass spectrometry procedure for the simultaneous determination of 12 mycotoxins in food, which were ochratoxin A, aflatoxins B1, B2, G1, G2, and M1, deoxynivalenol, zearalenone, fumonisins B1 and B2, and T-2 and HT-2 toxins. The method combined the simplicity of the QuEChERS (Quick, Easy, Cheap, Efficient, Rugged and Safe) approach with the efficiency of immunoaffinity column cleanup (the step used to enhance sensitivity and sample cleanup for some matrices only). Twenty-three entities were enrolled and were European reference laboratories for mycotoxin analysis, U.S. and European service laboratories, and Nestlé laboratories. Each participant analyzed 28 incurred and/or spiked blind samples composed of spices, nuts, milk powder, dried fruits, cereals, and baby food using the protocol given. Method performances were assessed according to ISO 5725-2. Relative standard deviations of repeatability and reproducibility and trueness values for each of the 115 mycotoxin/sample combinations ranged from 5% to 23%, 7% to 26%, and 85% to 129%, respectively, in line with requirements defined in EC 401/2006. The overall set of data gathered demonstrated that the method offered a unique platform to ensure compliance with EC 1881/2006 and EC 165/2013 regulations setting maximum limits for mycotoxins in food samples, even at low regulated levels for foods intended for infants and young children. The method was applicable regardless of the food, the regulated mycotoxin, and the concentration level, and thus is an excellent candidate for future standardization.

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Liquid Chromatographic Method for Determination of Iodine in Milk: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/76.4.711 ◽

1993 ◽

Vol 76 (4) ◽

pp. 711-719 ◽

Cited By ~ 3

Author(s):

David Sertl ◽

William Malone ◽

◽

P Beljaars ◽

C Blake ◽

...

Keyword(s):

Membrane Filter ◽

Collaborative Study ◽

Reversed Phase ◽

Powdered Milk ◽

Insoluble Material ◽

Relative Standard ◽

Repeatability And Reproducibility ◽

Standard Deviations ◽

Liquid Chromatographic

Abstract Nine laboratories participated in an AOAC International/ International Dairy Federation collaborative study on a liquid chromatographic (LC) method for determination of iodine in milk. Liquid milk is passed through a 25 000 MW membrane filter to remove protein and insoluble material. Iodine (in the form of iodide) in the clear filtrate is separated by reversed-phase ion-pair LC and is detected electrochemically. Participants analyzed 2 commercial pasteurized whole milks and 5 nonfat dry milk powders in blind duplicate. Each sample was tested in duplicate on 2 days. Repeatability and reproducibility standard deviations (sr and SR, respectively) and repeatability and reproducibility relative standard deviations (RSDr and RSDR, respectively) for determinations of iodine in whole milk (mean recovery, 86.7%) were as follows: sr, 22 μg/L; SR, 22 μg/L; RSDr, 8.2%; and RSDR, 8.3%. For powdered milk (mean recovery, 91 %), the values were as follows: sr, 0.14 μg/g; SR, 0.22 μg/g; RSDr, 9.0%; and RSDR, 12.7%. The method was adopted first action by AOAC International.

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Fluorometric Determination of Selenium in Foods

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/57.2.368 ◽

1974 ◽

Vol 57 (2) ◽

pp. 368-372 ◽

Cited By ~ 2

Author(s):

Milan Ihnat

Keyword(s):

Standard Deviation ◽

Milk Powder ◽

Skim Milk ◽

Skim Milk Powder ◽

Food Samples ◽

Fluorometric Method ◽

Fluorometric Determination ◽

Relative Standard ◽

The Mean

Abstract A fluorometric method using 2,3-diaminonaphthalene for estimating selenium has been evaluated with regard to its applicability to food samples. Charring of the sample during digestion appeared to result in losses of native and added selenium from some samples, so a modified wet digestion procedure was introduced. Digestion first in nitric acid followed by a mixture of nitric-perchloric-sulfuric acids substantially reduced the incidence of sample charring for a variety of foods. The mean apparent recovery of selenium added as selenite or selenate at 100 and 500 ng levels to 0.1 and 1.0 g corn cereal, skim milk powder, and meat and 0.1 g fish was 101.0%; the actual recovery of the same levels of selenium from standard solutions was 96.6%. For a variety of samples containing 5—750 ng native or added selenium, the standard deviation as 4.7 + 1.95 X 10-2W ng, where W = ng selenium in the sample taken for analysis. The relative standard deviation (RSD) as a function of selenium weight (ng) was 50% (10), 6.7% (100), 4.3% (200), 3.1% (400), 2.7% (600), and 2.5% (800). The detection limit (weight of selenium at which RSD = 50%) was 10 ng at a mean blank level of 25 ng.

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Determination of Metals in Foods by Atomic Absorption Spectrometry after Dry Ashing: NMKL1 Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/83.5.1204 ◽

2000 ◽

Vol 83 (5) ◽

pp. 1204-1211 ◽

Cited By ~ 93

Author(s):

Lars Jorhem ◽

G Afthan ◽

G Cumont ◽

H P Dypdahl ◽

K Gadd ◽

...

Keyword(s):

Standard Deviation ◽

Atomic Absorption Spectrometry ◽

Atomic Absorption ◽

Collaborative Study ◽

Milk Powder ◽

Absorption Spectrometry ◽

Relative Standard ◽

Dry Ashing ◽

Zinc Concentrations

Abstract A method for determination of lead, cadmium, zinc, copper, and iron in foods by atomic absorption spectrometry (AAS) after dry ashing at 450°C was collaboratively studied in 16 laboratories. The study was preceded by a practice round of familiarization samples and another round in which solutions were distributed and the metals were determined directly by AAS. The study included 5 different foods (liver paste, apple sauce, minced fish, wheat bran, and milk powder) and 2 simulated diets. A single analysis was carried out with each sample. Suitable sample combinations were used as split-level combinations for determination of the repeatability standard deviation. The reproducibility relative standard deviation for each of the elements ranged from 20 to 50% for lead concentrations of 0.040–0.25 mg/kg, from 12 to 352% for cadmium concentrations of 0.001–0.51 mg/kg, from 4 to 8% for zinc concentrations of 0.7–38 mg/kg, from 7 to 45% for copper concentrations of 0.51–45 mg /kg, and from 11 to 14% for iron concentrations of 4–216 mg/kg.

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Determination of the Cross-Reactivities for -Zearalenol, -Zearalenol, Zearalanone, -Zearalanol, and -Zearalanol on Three Commercial Immunoaffinity Columns Targeting Zearalenone

Journal of AOAC International ◽

10.1093/jaoac/90.4.1197 ◽

2007 ◽

Vol 90 (4) ◽

pp. 1197-1202 ◽

Cited By ~ 8

Author(s):

Marianne Erbs ◽

Nccolo Hartmann ◽

Thomas D Bucheli

Keyword(s):

Internal Standards ◽

River Water Samples ◽

Chromatography Tandem Mass Spectrometry ◽

Relative Standard ◽

Competition Effects ◽

Liquid Chromatography Tandem Mass ◽

Mycotoxin Analysis ◽

Immunoaffinity Columns ◽

Antibody Specificities

Abstract Immunoaffinity extraction has become increasingly important as a sample preparation and cleanup method in mycotoxin analysis. In this study, the antibody specificities of 3 commercial immunoaffinity columns (IACs) targeting zearalenone (ZON) were compared for -zearalenol, -zearalenol, zearalanone, -zearalanol, and -zearalanol. The recoveries of ZON and its 5 analogs were determined in triplicate when extracted from 10 mL circumneutral river water samples spiked with 20 ng analyte individually or in a mixture. The analytes were analyzed by means of electrospray ionization liquid chromatography/tandem mass spectrometry using deuterated internal standards for quantitation. Recoveries ranged from 69 to 115% for all analytes with relative standard deviations of 139%. Cross-reactivities for the analogs were >80% when applied both individually and in a mixture. No significant competition effects were observed when the compounds were applied as a multianalyte mixture well below the stated IAC capacities. The results obtained here demonstrate that all IACs tested are highly cross-reactive towards the 5 ZON derivatives and may be applied for their simultaneous extraction or cleanup.

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Detection of Five Mycotoxins in Different Food Matrices in the Malaysian Market by Using Validated Liquid Chromatography Electrospray Ionization Triple Quadrupole Mass Spectrometry

Toxins ◽

10.3390/toxins11040196 ◽

2019 ◽

Vol 11 (4) ◽

pp. 196 ◽

Cited By ~ 7

Author(s):

Ali Alsharif ◽

Yeun-Mun Choo ◽

Guan-Huat Tan

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Ochratoxin A ◽

Wheat Flour ◽

Food Samples ◽

Food Contaminants ◽

Relative Standard ◽

Liquid Chromatography Tandem Mass ◽

Food Matrices

Mycotoxins are common food contaminants which cause poisoning and severe health risks to humans and animals. The present study applied chemometric approach in liquid chromatography-tandem mass spectrometry (LC-MS/MS) optimization for simultaneous determination of mycotoxins, i.e., aflatoxins B1, B2, G1, and G2, and ochratoxin A. The validated quick, easy, cheap, effective, rugged, and safe (QuEChERS)-LC-MS/MS method was used to study the occurrence of mycotoxins in 120 food matrices. The recovery ranges from 81.94% to 101.67% with relative standard deviation (RSD) lesser than 11%. Through the developed method, aflatoxins were detected in raisin, pistachio, peanut, wheat flour, spice, and chili samples with concentration ranges from 0.45 to 16.93 µg/kg. Trace concentration of ochratoxin A was found in wheat flour and peanut samples which ranged from 1.2 to 3.53 µg/kg. Some of the tested food samples contained mycotoxins of above the European legal maximum limit.

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Gas Chromatographic Determination of Nicotine in Environmental Tobacco Smoke: Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/72.6.1002 ◽

1989 ◽

Vol 72 (6) ◽

pp. 1002-1006

Author(s):

Michael W Ogden

Keyword(s):

Environmental Tobacco Smoke ◽

Tobacco Smoke ◽

Collaborative Study ◽

Chromatographic Determination ◽

Selective Detection ◽

Mainstream Smoke ◽

Relative Standard ◽

Repeatability And Reproducibility ◽

Gas Chromatographic Method

Abstract A gas chromatographic method for determination of vapor phase nicotine in environmental tobacco smoke (ETS) was collaboratively studied by 6 laboratories. Nicotine is desorbed from XAD-4 sample tubes with ethyl acetate containing triethylamine and determined by gas chromatography with nitrogen-selective detection. Each collaborator received blind duplicate samples at each of 6 nicotine concentrations. Three concentrations were generated by spiking XAD-4 tubes with known amounts of nicotine; the remaining 3 concentrations were ETS samples obtained in a carefully controlled environmental chamber containing sidestream and exhaled mainstream smoke from 1R4F Kentucky reference cigarettes. Repeatability and reproducibility relative standard deviations ranged from 4.4 to 11.1% and from 7.0 to 11.1%, respectively, for nicotine concentrations evaluated (up to 6 ng/cu m). The method has been adopted official first action.

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Determination of Total Phosphorus in Foods by Colorimetry: Summary of NMKL Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/79.6.1408 ◽

1996 ◽

Vol 79 (6) ◽

pp. 1408-1410 ◽

Cited By ~ 2

Author(s):

T Katrhna Pulliainen ◽

Harriet C Wallin

Keyword(s):

Total Phosphorus ◽

Phosphorus Content ◽

Collaborative Study ◽

Colorimetric Method ◽

Milk Powder ◽

Molybdenum Blue ◽

Relative Standard ◽

Standard Deviations ◽

Skimmed Milk Powder

Abstract A collaborative study was conducted to validate a spectrophotometric–colorimetric method for determining total phosphorus in foods. The sample was dry-ashed in the presence of zinc oxide, and total phosphorus content was measured colorimetrically as molybdenum blue. Twelve laboratories from the Nordic countries participated in the study. The test materials included potato flour, sausage, cold ham, infant formula powder, cheese, and skimmed milk powder. Participants received 12 randomly coded samples of 2 blind duplicates of each material. Phosphorus contents of materials varied between 0.076 and 0.96 g/100 g. Relative standard deviations for repeatability of the method varied from 1.1% for 0.96 g phosphorus/100 g to 5.4% for 0.29 g phosphorus/100 g. Relative standard deviations for reproducibility varied from 3.6% for 0.96 g phosphorus/100 g to 7.7% for 0.23 g phosphorus/100 g. The colorimetric method for determination of total phosphorus in foods has been adopted first action by AOAC INTERNATIONAL as an NMKUAOAC INTERNATIONAL method.

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Liquid Chromatographic Method for Multiresidue Determination of Benzimidazoles in Beef Liver and Muscle: Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/74.3.487 ◽

1991 ◽

Vol 74 (3) ◽

pp. 487-493 ◽

Cited By ~ 4

Author(s):

Leon W Levan ◽

Charlie J Barnes

Keyword(s):

Chromatographic Method ◽

Collaborative Study ◽

Study Data ◽

Beef Liver ◽

Liquid Chromatographic Method ◽

Relative Standard ◽

Repeatability And Reproducibility ◽

Multiresidue Determination ◽

Liquid Chromatographic

Abstract A liquid chromatographic method for determination of thiabendazole, 5-hydroxythiabendazole, oxfendazole, mebendazole (MBZ), and fenbendazole (FBZ) In cattle liver and muscle was collaboratively studied in 7 laboratories In 1986. For blind fortified samples containing 800 ppb FBZ, average recovery and relative standard deviations for repeatability and reproducibility (RSDr and RSDR) based on results from 6 of the participating laboratories were 83%, 12.7%, and 14.0%, respectively. Recoveries of FBZ from incurred liver samples were more variable. Recoveries of MBZ from livers fortified at the 100 ppb level were encouraging; however, the drug levels were too low in the incurred samples used for MBZ studies. Except for FBZ and MBZ In liver, the study data were not satisfactory. The method has been adopted official first action by AOAC for determination of 800-1600 ppb fenbendazole In liver. The analysis should be repeated using a smaller sample size when Initial analyses show levels greater than 1600 ppb FBZ.

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Determination of Methylcellulose and Hydroxypropyl Methylcellulose Food Gums in Food and Food Products: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/90.3.786 ◽

2007 ◽

Vol 90 (3) ◽

pp. 786-793 ◽

Cited By ~ 7

Author(s):

Robert G Harfmann ◽

Balasaheb K Deshmukh ◽

Jerry Conklin ◽

Maciej Turowski ◽

Stephanie Lynch ◽

...

Keyword(s):

Standard Deviation ◽

Relative Standard Deviation ◽

Hydroxypropyl Methylcellulose ◽

Collaborative Study ◽

Food Samples ◽

Size Exclusion ◽

Official Method ◽

Relative Standard ◽

Aoac Official

Abstract A collaborative study was performed to determine the reproducibility of a method for the determination of methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC) in food. These widely used food gums possess unusual solubility characteristics and cannot accurately be determined by existing dietary fiber methods. The new method uses the enzyme-digestion procedure of AOAC Official Method 991.43. Digestate solutions must be refrigerated to fully hydrate MC or HPMC. The chilled solutions are filtered and analyzed by size-exclusion liquid chromatography. Collaborating laboratories received 28 samples containing MC or HPMC in the range of 0100%. The sample set included blind duplicates of 5 food matrixes (bread, milk, fish, potato, and powdered juice drink). Cochran and Grubbs tests were used to eliminate outliers. For food samples containing MC, values for within-laboratory precision, repeatability relative standard deviation (RSDr), ranged from 4.2 to 16%, and values for among-laboratories precision, reproducibility relative standard deviation (RSDR), ranged from 11 to 20%. For HPMC samples, RSDr values ranged from 6.4 to 27%, and RSDR values ranged from 17 to 39%. Recoveries of MC and HPMC from the food matrixes ranged from 78 to 101%. These results show acceptable precision and reproducibility for the determination of MC and HPMC, for which no Official AOAC Methods exist. It is recommended that this method be adopted as AOAC Official First Action.

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Determination of Fumonisins B1 and B2 in Corn and Corn Flakes by Liquid Chromatography with Immunoaffinity Column Cleanup: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/84.6.1828 ◽

2001 ◽

Vol 84 (6) ◽

pp. 1828-1838 ◽

Cited By ~ 80

Author(s):

Angelo Visconti ◽

Michele Solfrizzo ◽

Annalisa De Girolamo ◽

H Bresch ◽

P Burdaspal ◽

...

Keyword(s):

Collaborative Study ◽

Immunoaffinity Column ◽

Relative Standard ◽

Repeatability And Reproducibility ◽

Double Extraction ◽

Standard Deviations ◽

Corn Flakes ◽

Liquid Chromatographic ◽

Fumonisins B1 And B2

Abstract A liquid chromatographic (LC) method for the determination of fumonisins B1 (FB1) and B2 (FB2) in corn and corn flakes was collaboratively studied by 23 laboratories, which analyzed 5 blind duplicate pairs of each matrix to establish the accuracy, repeatability, and reproducibility characteristics of the method. Fumonisin levels in the corn ranged from <0.05 (blank) to 1.41 μg/g for FB1 and from <0.05 to 0.56 μg/g for FB2, whereas in the corn flakes they ranged from <0.05 to 1.05 μg/g for FB1 and from <0.05 to 0.46 μg/g for FB2. The method involved double extraction with acetonitrile–methanol–water (25 + 25 + 50), cleanup through an immunoaffinity column, and LC determination of the fumonisins after derivatization with o-phthaldialdehyde. Relative standard deviations for the within-laboratory repeatability (RSDr) of the corn analyses ranged from 19 to 24% for FB1 and from 19 to 27% for FB2; for the corn flakes analyses, RSDr ranged from 9 to 21% for FB1 and from 8 to 22% for FB2. Relative standard deviations for the between-laboratories reproducibility (RSDR) of the corn analyses ranged from 22 to 28% for FB1 and from 22 to 30% for the FB2; for corn flakes analyses, RSDR ranged from 27 to 32% for FB1 and from 26 to 35% for FB2. Mean recoveries of FB1 and FB2 from corn spiked with FB1 at 0.80 μg/g and with FB2 at 0.40 μg/g were 76 and 72%, respectively; for corn flakes spiked at the same levels recoveries were 110 and 97% for FB1 and FB2, respectively. HORRAT ratios for the analyses of corn ranged from 1.44 to 1.53 for FB1 and from 0.96 to 1.48 for FB2, whereas for corn flakes they ranged from 1.60 to 1.82 for FB1 and from 1.39 to 1.68 for FB2.

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