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1.
J AOAC Int ; 107(4): 617-631, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38627236

ABSTRACT

BACKGROUND: The presence of veterinary drug residues in food-producing animals and animal products is regulated through the enforcement of maximum residue limits (MRLs). To answer the need of the food sector to monitor these substances in a wide range of food commodities, stakeholders at AOAC INTERNATIONAL identified the need for a reliable confirmatory screening method. Such a qualitative approach is required for compliance checking and to support product release in manufacturing. OBJECTIVE: Data were collected from five independent laboratories that applied the First Action Official Method 2020.04 to demonstrate adequate performance under reproducibility conditions. The probability of detection (POD) was calculated in blank test samples and test samples spiked at the screening target concentration (STC) level, with the objective to achieve PODs ≤10% and ≥90%, respectively. Additionally, the effectiveness of the screening method was evaluated by participating in 92 proficiency tests. METHODS: Four streams were optimized to screen for 152 veterinary drug residues by LC-MS/MS in a wide variety of food commodities including milk-based ingredients and related products (e.g., milk fractions, infant formula, infant cereals, and baby foods), meat- and fish-based ingredients and related products (fresh, powdered, cooked, infant cereals, and baby foods), and other ingredients based on eggs, animal fat, and animal byproducts. The four streams covered 105 antibiotic residues, anti-inflammatory and antiparasitic agents (stream A), 23 beta-lactams (stream B), 14 aminoglycosides (stream C), and 10 tetracyclines (Stream D). RESULTS: The multilaboratory validation led to PODs at the STC ≥94% and PODs in the blank ≤9%. Further application of the multilaboratory validated method to 92 proficiency tests provided more than 99% satisfactory submitted results (n = 784). CONCLUSION: The interlaboratory reproducibility determined for this method met the acceptance criteria defined in AOAC Standard Method Performance Requirement (SMPR®) 2018.010. HIGHLIGHTS: AOAC has approved the method for Final Action status.


Subject(s)
Drug Residues , Food Contamination , Tandem Mass Spectrometry , Veterinary Drugs , Drug Residues/analysis , Veterinary Drugs/analysis , Tandem Mass Spectrometry/methods , Animals , Food Contamination/analysis , Chromatography, Liquid/methods , Milk/chemistry , Reproducibility of Results , Meat/analysis , Food Analysis/methods , Liquid Chromatography-Mass Spectrometry
2.
J AOAC Int ; 107(3): 453-463, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38273660

ABSTRACT

BACKGROUND: Acrylamide (AA) is a process contaminant naturally formed during the cooking of starchy food at high temperatures. Considering existing risks of misquantification inherent to the analysis of AA, an AOAC initiative raised the need for a consensus standard to determine AA in a broad variety of food. OBJECTIVE: A quantitative LC-MS/MS method for AA determination in food was validated in a single-laboratory study. Targeted performance requirements in terms of target matrixes, limit of quantification, recovery, and precision were as defined per Standard Method Performance Requirement (SMPR®) 2022.006. METHOD: The proposed method derives from EN 16618:2015 standard pending modifications brought to the (1) sample preparation (simplified, potentially automated); (2) scope of application (significantly extended); and (3) LC conditions (improved selectivity). Confirmatory detection of AA is conducted by LC-MS/MS in the Selected Reaction Monitoring mode (SRM), and isotopic dilution was applied for quantification approach using either 2,3,3-d3-acrylamide (d3-AA), or 13C3-2,3,3-d3-acrylamide (13C3-d3-AA) as labeled internal standard. RESULTS: A total of 16 laboratory samples from nine matrix categories were included in the validation process. A full validation was conducted on coffee (instant, roast), infant cereal, cocoa powder, pet food (croquettes), tea (green tea), spices (black pepper), and nuts (roasted almonds) with satisfactory performances both in terms of recovery (97-108%) and precision (RSDr and RSDiR <12%). The method applicability was further demonstrated through the analysis of quality control materials and reference materials including French fries, potato crisps, vegetable crisps, instant coffee, infant food, and biscuits (cookies), with accuracy values determined within a 94-107% range. CONCLUSIONS: The performances of the presented method are in agreement with the acceptance criteria stipulated in SMPR 2022.006. HIGHLIGHTS: The Expert Review Panel for acrylamide approved the present method as AOAC Official First Action 2023.01.


Subject(s)
Acrylamide , Cacao , Coffee , Edible Grain , Food Contamination , Infant Food , Nuts , Solanum tuberosum , Tandem Mass Spectrometry , Tea , Acrylamide/analysis , Tandem Mass Spectrometry/methods , Tea/chemistry , Coffee/chemistry , Chromatography, Liquid/methods , Solanum tuberosum/chemistry , Edible Grain/chemistry , Food Contamination/analysis , Nuts/chemistry , Cacao/chemistry , Infant Food/analysis , Spices/analysis , Food Analysis/methods , Chocolate/analysis , Vegetables/chemistry , Animals , Animal Feed/analysis , Liquid Chromatography-Mass Spectrometry
3.
Article in English | MEDLINE | ID: mdl-36098978

ABSTRACT

Liquid chromatography-high resolution mass spectrometry (LC-HRMS) is considered an unavoidable extension of low-resolution LC-MS/MS that stretches the capabilities of multi-residue analysis of chemical contaminants in food. However, LC-HRMS acquisitions generate a massive amount of information available for data processing with supplier software that still miss critical calculation features and adapted reporting tools. Consequently, routine laboratories are still reluctant to switch from LC-MS/MS to LC-HRMS, the latter is still perceived as a cumbersome and demanding technology. In that context, we propose a four-step LC-HRMS workflow to speed-up data processing in situations of multi-residue multi-matrix analysis with the goal to maximize the time spent on data interpretation rather than on data formatting. The first three steps of the workflow imply specific settings on the Orbitrap HRMS associated software (TraceFinderTM) while the fourth step is the novelty i.e. a newly coded R-script capable to translate a raw export file into a comprehensive .xlsx report file in a few seconds. As recommended by various international guidelines and in some official methods, standard addition-based applications are fully embedded in this reporting tool whilst still being the main bottleneck of supplier's software. The reporting tool also allows appropriate data formatting, filtering, and color-coding options to provide a clear picture of compounds being detected or not, and those requiring specific attention due to unmet quality control criteria as required by European legislation (European Commission SANTE 11312/2021). It is hoped that additional functionalities compatible with R scripts will be soon fully embedded in the supplier's software for easier data interpretation and reporting.


Subject(s)
Software , Tandem Mass Spectrometry , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Quality Control , Laboratories
4.
Article in English | MEDLINE | ID: mdl-35113763

ABSTRACT

Acrylamide is prone to misquantification, and critical steps in the analytical procedures need to be identified and controlled to ensure a reliable determination. Four methods were considered to illustrate misquantification issues with acrylamide. For two methods varying by the extent of their sample preparations, cases of overestimation in cocoa samples reaching up to a 20-fold factor are shown. A second example, applied to a variety of food products, includes two other methods varying by their chromatographic conditions. As a follow up of a study conducted in 2020 about the identification of N-acetyl-ß-alanine as an interference of acrylamide in coffee, the extent of this interference was evaluated in a selection of coffee samples, cereal-based products and baby foods. The ultimate objective of this manuscript was to resolve such cases of misquantification and validate a wide scope and robust method allowing an interference free acrylamide analysis. To do so, an extraction procedure based on the EN 16618:2015 standard with water extraction and two consecutive solid phase extraction (SPE) steps was applied with modified liquid chromatographic conditions. The method was validated in coffee, cereals, baby foods, cocoa and pet foods with excellent performance in terms of recovery (97-108%) and precision (RSDr and RSDiR <12 %). The breath of scope was further proved through trueness determination in quality control materials and reference materials including French fries, potato crisps, vegetable crisps, instant coffee, infant food and biscuit (cookie), with trueness values found within a 94-107% range.


Subject(s)
Acrylamide , Cacao , Acrylamide/analysis , Chromatography, Liquid/methods , Coffee/chemistry , Consensus , Edible Grain/chemistry , Food Contamination/analysis , Humans , Tandem Mass Spectrometry/methods
5.
J AOAC Int ; 104(3): 650-681, 2021 Jun 12.
Article in English | MEDLINE | ID: mdl-33351146

ABSTRACT

BACKGROUND: Veterinary drug residues in food are substances (>200 compounds) exhibiting potential health risks for consumers, thus being regulated in national legislations and the Codex Alimentarius. Most of the compounds are regulated based upon a maximum residue limit (MRL) while a few of them are banned in food for humans. The food sector needs a reliable and consensus analytical platform able to monitor these substances in a wide range of food commodities. OBJECTIVE: Several confirmatory methods based on liquid chromatography-mass spectrometry are available in the literature for either screening or quantification of veterinary drug residues in food, but usually applicable to limited scope of matrices. The current work describes the single-laboratory validation (SLV) of a method for screening 154 veterinary drug residues in several food categories. METHODS: This work describes a streamlined platform making use of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for screening 105 antibiotics, 41 antiparasitics, 5anti-inflammatory agents, and 3 tranquilizers in foods of animal origin. For the best performance across the commodities (dairy-, meat-, fish-, and egg-based materials), four method streams were established. As a screening tool, probabilities of detection (PODs) were assessed at the screening target concentration (STC < MRL) and the blank. RESULTS: The SLV led to PODs at the STC >94% and PODs in the blank < 4%. CONCLUSION: Performance is in agreement with the acceptance criteria defined in SMPR 2018.010. HIGHLIGHTS: The Expert Review Panel approved the present method as AOAC Official First Action 2020.04.


Subject(s)
Drug Residues , Veterinary Drugs , Animals , Chromatography, Liquid , Drug Residues/analysis , Food Contamination/analysis , Humans , Meat/analysis , Tandem Mass Spectrometry , Veterinary Drugs/analysis
6.
J Agric Food Chem ; 68(29): 7727-7733, 2020 Jul 22.
Article in English | MEDLINE | ID: mdl-32578985

ABSTRACT

The study reports the role of choline and compounds thereof in the formation of chlormequat under thermal conditions, with emphasis on the molecular mechanism involved in the transformation. The data show the decomposition of choline to chlormequat at 200 °C in presence of chloride ions, likely by nucleophilic substitution. Furthermore, the results suggest that phosphatidylcholine, glycerophosphocholine, and phosphocholine are the effective precursors of chlormequat under sufficient thermal conditions due to their capability to degrade to choline and/or the ability of the phosphate moiety to behave as a good leaving group with respect to nucleophilic attacks. Thermal treatments (120 and 200 °C) applied to egg powder, rich in phosphatidylcholine, and wheat flour, with choline at a substantial level, suggest that less energy is required for obtaining chlormequat from phosphatidylcholine than from choline. This observation is consistent with the postulated mechanism of a nucleophilic substitution with phosphate moieties acting as better leaving groups than the hydroxyl group.


Subject(s)
Chlormequat/analysis , Eggs/analysis , Flour/analysis , Plant Growth Regulators/analysis , Triticum/chemistry , Animals , Chickens , Choline/analysis , Hot Temperature
7.
Food Chem ; 303: 125406, 2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31472386

ABSTRACT

This study reports the heat-induced formation of furan by decarboxylation of 2-furoic acid, and 2-methylfuran by dehydration of furfuryl alcohol under dry conditions. Model systems were incubated at temperatures up to 190 °C, followed by quantitative determination of furan and 2-methylfuran performed by isotope dilution headspace gas chromatography-mass spectrometry. Results show that 2-furoic acid decarboxylation and furfuryl alcohol dehydration are activated as from about 140-160 °C. Furfuryl alcohol and 2-furoic acids were measured in a selection of roasted coffee products by isotope dilution liquid chromatography-high resolution mass spectrometry, and the data evidenced a strong correlation between the two compounds, suggesting an intimate mechanistic relationship between them. The possible oxidation of furfuryl alcohol to furfural and 2-furoic acid in heated food is raised with particular emphasis on coffee roasting. These findings are relevant for better understanding the formation of furan and alkylfurans in food, and ultimately opening avenues for mitigation.


Subject(s)
Furans/analysis , Furans/chemistry , Coffea/chemistry , Cooking , Food Contamination/analysis , Gas Chromatography-Mass Spectrometry/methods , Hot Temperature , Seeds/chemistry
8.
J Chromatogr A ; 1610: 460566, 2020 Jan 11.
Article in English | MEDLINE | ID: mdl-31582163

ABSTRACT

Analysis of acrylamide in coffee by liquid chromatography-tandem mass spectrometry (LC-MS/MS) is prone to interferences. According to our study, unknown background ions can entail an overestimation by up to 40% in case of coelution with acrylamide. In order to develop a precise and accurate quantification method for acrylamide, identification and removal of these interfering ions is requested. We thus studied potential isobaric impurities of acrylamide using liquid chromatography-high resolution mass spectrometry (LC-HRMS). An in-source fragment of N-Acetyl-ß-alanine, a substance not yet reported in coffee, was identified as the main interfering ion. The characterization of the interference further triggered modification of the mobile phase-pH to alter the retention of N-Acetyl-ß-alanine and achieve an interference free acrylamide determination. Two other compounds closely related to acrylamide namely 3-aminopropanamide and lactamide were also susceptible to in-source fragmentation, highlighting the pivotal role of chromatographic conditions to ensure a reliable quantification of acrylamide.


Subject(s)
Acrylamide/analysis , Chromatography, Liquid/methods , Coffee/chemistry , Tandem Mass Spectrometry/methods , Reference Standards , Solvents/chemistry , beta-Alanine/analysis
9.
Toxins (Basel) ; 11(11)2019 11 12.
Article in English | MEDLINE | ID: mdl-31726655

ABSTRACT

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.


Subject(s)
Chromatography, Liquid/methods , Food Contamination/analysis , Mycotoxins/analysis , Tandem Mass Spectrometry/methods , Child, Preschool , Enzyme-Linked Immunosorbent Assay , Humans , Infant , Infant Food , International Cooperation , Limit of Detection , Reproducibility of Results
10.
Article in English | MEDLINE | ID: mdl-29451850

ABSTRACT

An LC-MS/MS method for screening 14 aminoglycosides in foodstuffs of animal origin is presented. Its scope includes raw materials and processed ingredients but also finished products composed of milk, meat, fish, egg or fat. Aminoglycosides are extracted in an acidic aqueous solution, which is first recovered after centrifugation, then diluted with a basic buffer and finally purified by molecularly imprinted polymer-solid phase extraction (MIP-SPE). Analytes are detected within 8 min by ion-pair reversed phase LC-MS/MS. Due to the large range of foodstuffs involved, the variability of matrix effects led to significant MS signal variations. This was circumvented by systematically extracting each sample twice, i.e. 'unspiked' and 'spiked' at the screening target concentration of 50 µg kg-1. The method was validated according to the European Community Reference Laboratories Residues Guidelines giving false-negative and false-positive rates ≤3% for all compounds. Ruggedness of the method was further demonstrated in quality control operations by a second laboratory. The 14 aminoglycosides in water-based standard solutions were stable for up to 6 months when stored at either -80°C, -20°C or at 4°C storage temperatures.


Subject(s)
Aminoglycosides/analysis , Food Analysis , Food Contamination/analysis , Molecular Imprinting , Polymers/chemistry , Solid Phase Extraction , Animals , Chromatography, Liquid , Tandem Mass Spectrometry
11.
Article in English | MEDLINE | ID: mdl-29324075

ABSTRACT

Regulatory agencies and government authorities have established maximum residue limits (MRL) in various food matrices of animal origin for supporting governments and food operators in the monitoring of veterinary drug residues in the food chain, and ultimately in the consumer's plate. Today, about 200 veterinary drug residues from several families, mainly with antibiotic, antiparasitic or antiinflammatory activities, are regulated in a variety of food matrices such as milk, meat or egg. This article provides a review of the regulatory framework in milk and muscle including data from Codex Alimentarius, Europe, the U.S.A., Canada and China for about 220 veterinary drugs. The article also provides a comprehensive overview of the challenge for food control, and emphasizes the pivotal role of liquid chromatography-mass spectrometry (LC-MS), either in tandem with quadrupoles (LC-MS/MS) or high resolution MS (LC-HRMS), for ensuring an adequate consumer protection combined with an affordable cost. The capability of a streamlined LC-MS/MS platform for screening 152 veterinary drug residues in a broad range of raw materials and finished products is highlighted in a production line perspective. The rationale for a suite of four methods intended to achieve appropriate performance in terms of scope and sensitivity is presented. Overall, the platform encompasses one stream for the determination of 105 compounds in a run (based on acidic QuEChERS-like), plus two streams for 23 ß-lactams (alkaline QuEChERS-like) and 10 tetracyclines (low-temperature partitioning), respectively, and a dedicated stream for 14 aminoglycosides (molecularly-imprinted polymer).


Subject(s)
Drug Residues/analysis , Food Analysis , Food Contamination/analysis , Tandem Mass Spectrometry , Veterinary Drugs/analysis , Animals , Chromatography, Liquid , Humans
12.
Article in English | MEDLINE | ID: mdl-29324077

ABSTRACT

A fast and robust high performance LC-MS/MS screening method was developed for the analysis of ß-lactam antibiotics in foods of animal origin: eggs, raw milk, processed dairy ingredients, infant formula, and meat- and fish-based products including baby foods. QuEChERS extraction with some adaptations enabled 23 drugs to be simultaneously monitored. Screening target concentrations were set at levels adequate to ensure compliance with current European, Chinese, US and Canadian regulations. The method was fully validated according to the European Community Reference Laboratories Residues Guidelines using 93 food samples of different composition. False-negative and false-positive rates were below 5% for all analytes. The method is adequate for use in high-routine laboratories. A 1-year study was additionally conducted to assess the stability of the 23 analytes in the working standard solution.


Subject(s)
Alkalies/chemistry , Food Analysis , Food Contamination/analysis , Infant Formula/analysis , beta-Lactams/analysis , Animals , Chromatography, Liquid , Humans , Infant , Tandem Mass Spectrometry
13.
Article in English | MEDLINE | ID: mdl-29337659

ABSTRACT

An LC-MS/MS method is presented for screening five tetracyclines and their epimers in a broad range of food products. The scope of matrices includes meat-, fish-, seafood-based products, various dairy ingredients, infant formulae and fats. The method principle is based on a liquid-liquid extraction with aqueous ethylenediaminetetraacetic acid (EDTA) and acetonitrile followed by a freezing step to promote phase separation at low temperature. After defatting with hexane, sample extracts were evaporated and reconstituted before injection onto the LC-MS/MS system. The addition of oxalic acid in the aqueous mobile phase was mandatory to maintain good peak shape and sensitivity over the run. The screening is based upon a double preparation of each sample, one 'as such' and a second one with the analytes spiked in the sample, in order to mitigate the risk of false negative response. The method was validated according to the European Community Reference Laboratories Residues Guidelines. A total of 93 samples were included in the validation by two independent laboratories giving both false-negative and false-positive rates at 0% for all compounds. Over the last two years, 2600 samples were analysed routinely and only one chicken sample was found above the regulatory limit.


Subject(s)
Food Analysis , Food Contamination/analysis , Liquid-Liquid Extraction , Tandem Mass Spectrometry , Temperature , Tetracyclines/analysis , Tetracyclines/chemistry , Chromatography, Liquid
14.
Article in English | MEDLINE | ID: mdl-29346035

ABSTRACT

A procedure for screening 105 veterinary drugs in foods by liquid chromatography tandem mass-spectrometry (LC-MS/MS) is presented. Its scope encompasses raw materials of animal origin (milk, meat, fish, egg and fat) but also related processed ingredients and finished products commonly used and manufactured by food business operators. Due to the complexity of the matrices considered and to efficiently deal with losses during extraction and matrix effects during MS source ionisation, each sample was analysed twice, that is 'unspiked' and 'spiked at the screening target concentration' using a QuEChERS-like extraction. The entire procedure was validated according to the European Community Reference Laboratories Residues Guidelines. False-negative and false-positive rates were below 5% for all veterinary drugs whatever the food matrix. Effectiveness of the procedure was further demonstrated through participation to five proficiency tests and its ruggedness demonstrated in quality control operations by a second laboratory.


Subject(s)
Anti-Bacterial Agents/analysis , Anti-Inflammatory Agents/analysis , Antiparasitic Agents/analysis , Food Contamination/analysis , Tranquilizing Agents/analysis , Veterinary Drugs/analysis , Animals , Chromatography, Liquid , Food Analysis , Hydrogen-Ion Concentration , Tandem Mass Spectrometry
15.
Article in English | MEDLINE | ID: mdl-29377759

ABSTRACT

A study on stability of veterinary drugs in standard solutions stored at -80°C and at -20°C was conducted over 1 year. Data were acquired on 152 individual stock standard solutions and also on 15 family mixes and 2 working standard solutions. All solutions were prepared, stored and compared 1 year later against freshly prepared ones by LC-MS/MS. A statistical analysis was performed to set the acceptability criteria, taking into account the variability of standard preparations. In individual stock standard solutions stored at -80°C (12 months) and -20°C (9 months), stability was demonstrated for 141 and 140 out of 152 compounds, i.e. for 92% and 93% of compounds, respectively. Drugs were even more stable when solubilised in either diluted family mixes or working standard solutions, with more than 99% and 94% of compounds found unaltered when stored at -80°C and at -20°C, respectively. In mixes, beta-lactams from the cephalosporin (cefadroxil and cephalexin) and penicillin (amoxicillin and ampicillin) families were found to be the least stable compounds when stored at -20°C (6 months), necessitating storage at -80°C to achieve a 1-year shelf life. The study also evidenced solubility issues for two sulfonamides (sulfadiazine and sulfamerazine) in methanol-based solutions. An independent stability study conducted by a second laboratory confirmed the 1-year stability of 3 family mixes-quinolones, sulfonamides and tetracyclines.


Subject(s)
Food Analysis , Food Contamination/analysis , Veterinary Drugs/analysis , Veterinary Drugs/chemistry , Chromatography, Liquid , Drug Evaluation, Preclinical , Drug Stability , Solutions/standards , Tandem Mass Spectrometry , Temperature
16.
J Chromatogr A ; 1337: 75-84, 2014 Apr 11.
Article in English | MEDLINE | ID: mdl-24636559

ABSTRACT

Optimization and validation of a multi-mycotoxin method by LC-MS/MS is presented. The method covers the EU-regulated mycotoxins (aflatoxins, fumonisins, ochratoxin A, deoxynivalenol, zearalenone, T-2 and HT-2), as well as nivalenol and 3- and 15-acetyldeoxynivalenol for analysis of cereals, cocoa, oil, spices, infant formula, coffee and nuts. The proposed procedure combines two clean-up strategies: First, a generic preparation suitable for all mycotoxins based on the QuEChERS (for quick, easy, cheap, effective, rugged and safe) protocol. Second, a specific clean-up devoted to aflatoxins and ochratoxin A using immunoaffinity column (IAC) clean-up. Positive identification of mycotoxins in matrix was conducted according to the confirmation criteria defined in EU Commission Decision 2002/657/EC while quantification was performed by isotopic dilution using (13)C-labeled mycotoxins as internal standards. Limits of quantification were at or below the maximum levels set in the EC/1886/2006 document for all mycotoxin/matrix combinations under regulation. In particular, the inclusion of an IAC step allowed achieving LOQs as low as 0.05 and 0.25µg/kg in cereals for aflatoxins and ochratoxin A, respectively. Other performance parameters like linearity [(r)(2)>0.99], recovery [71-118%], precision [(RSDr and RSDiR)<33%], and trueness [78-117%] were all compliant with the analytical requirements stipulated in the CEN/TR/16059 document. Method ruggedness was proved by a verification process conducted by another laboratory.


Subject(s)
Mycotoxins/analysis , Cacao/chemistry , Carbon Isotopes , Chromatography, High Pressure Liquid/methods , Coffee/chemistry , Humans , Indicator Dilution Techniques , Infant , Infant Food , Infant, Newborn , Laboratory Proficiency Testing , Quality Control , Sensitivity and Specificity , Spices/analysis , Tandem Mass Spectrometry/methods
17.
J Agric Food Chem ; 59(14): 7659-65, 2011 Jul 27.
Article in English | MEDLINE | ID: mdl-21699174

ABSTRACT

A liquid chromatography electrospray ionization tandem mass spectrometry method for the determination of patulin in apple- and pear-based foodstuffs was developed. The sample preparation is based on the QuEChERS procedure involving an initial extraction step with water and acetonitrile, followed by a partitioning step after the addition of magnesium sulfate and sodium chloride. The cleanup was performed by using dispersive solid-phase extraction with a mixture of magnesium sulfate, primary secondary amine sorbent, and n-octadecylsiloxane sorbent added together to the extract. The cleaned extract was finally evaporated and reconstituted in water prior to injection. Quantitation was performed by isotope dilution using ((13)C(7))-patulin as internal standard. The method was first fully validated in three different baby food products including apple-pear juice, apple-pear puree, and infant cereals. Then the scope of application of the method was extended to pear concentrate, raw apples, apple flakes (naturally contaminated), dried apples, and yogurt. The sensitivity achieved by the method in all matrices gave limits of detection (LOD) and quantitation (LOQ) of ≤0.5 and ≤10 µg/kg, respectively, which was compliant with maximum levels settled in Commission Regulation (EC) No. 1881/2006. Method performances for all matrices also fulfilled the criteria established in the CEN/TR 16059:2010 document. Indeed, recoveries were within the 94-104% range; relative standard deviations of repeatability (RSD(r)) and intermediate reproducibility (RSD(IR)) were ≤7.5 and ≤13.0%, respectively, and trueness in an infant apple drink (FAPAS 1642) was measured at 99%.


Subject(s)
Chromatography, High Pressure Liquid/methods , Food Contamination/analysis , Malus/chemistry , Patulin/analysis , Pyrus/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Infant Food/analysis , Patulin/isolation & purification , Solid Phase Extraction , Tandem Mass Spectrometry/methods
18.
J Agric Food Chem ; 58(22): 11574-9, 2010 Nov 24.
Article in English | MEDLINE | ID: mdl-21038852

ABSTRACT

As a consequence of the adulteration of infant formulas and milk powders with melamine (MEL) in China in 2008, much attention has been devoted to the analysis of MEL [and cyanuric acid (CA)] in dairy products. Several methods based on high-performance liquid chromatography (HPLC), liquid chromatography-tandem mass spectrometry (LC-MS/MS), nuclear magnetic resonance (NMR), or Raman spectroscopy have been described in the literature. However, no method is available for the simultaneous determination of MEL and CA in other raw materials, which are considered as high-risk materials for economically motivated adulteration. The present paper reports the results of an interlaboratory-based performance evaluation conducted with seven laboratories worldwide. The purpose was to demonstrate the ability of a cleanup-free LC-MS/MS method, originally developed for cow's milk and milk-powdered infant formula, to quantify MEL and CA in egg powder and soy protein. Limit of detection (LOD) and limit of quantification (LOQ) were 0.02 and 0.05 mg/kg for MEL in egg powder and soy protein, respectively. For CA, LOD and LOQ were 0.05 and 0.10 mg/kg in egg powder and 1.0 and 1.50 mg/kg in soy protein, respectively. Recoveries ranged within a 97-113% range for both MEL and CA in egg powder and soy protein. Reproducibility values (RSD(R)) from seven laboratories were within a 5.4-11.7% range for both analytes in the considered matrices. Horwitz ratio (HorRat) values between 0.4 and 0.7 indicate acceptable among-laboratory precision for the method described.


Subject(s)
Chromatography, High Pressure Liquid/methods , Eggs/analysis , Infant Formula/chemistry , Milk/chemistry , Soybean Proteins/analysis , Tandem Mass Spectrometry/methods , Triazines/analysis , Animals , Cattle , Chickens , Food Contamination/analysis
19.
Mol Nutr Food Res ; 54(12): 1722-33, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20589860

ABSTRACT

SCOPE: Coffee is among the most frequently consumed beverages. Its consumption is inversely associated to the incidence of diseases related to reactive oxygen species; the phenomenon may be due to its antioxidant properties. Our primary objective was to investigate the impact of consumption of a coffee containing high levels of chlorogenic acids on the oxidation of proteins, DNA and membrane lipids; additionally, other redox biomarkers were monitored in an intervention trial. METHODS AND RESULTS: The treatment group (n=36) consumed instant coffee co-extracted from green and roasted beans, whereas the control consumed water (800 mL/P/day, 5 days). A global statistical analysis of four main biomarkers selected as primary outcomes showed that the overall changes are significant. 8-Isoprostaglandin F2α in urine declined by 15.3%, 3-nitrotyrosine was decreased by 16.1%, DNA migration due to oxidized purines and pyrimidines was (not significantly) reduced in lymphocytes by 12.5 and 14.1%. Other markers such as the total antioxidant capacity were moderately increased; e.g. LDL and malondialdehyde were shifted towards a non-significant reduction. CONCLUSION: The oxidation of DNA, lipids and proteins associated with the incidence of various diseases and the protection against their oxidative damage may be indicative for beneficial health effects of coffee.


Subject(s)
Chlorogenic Acid/analysis , Coffee/chemistry , DNA Damage , Macromolecular Substances/toxicity , Oxidative Stress , Adult , Antioxidants/metabolism , Comet Assay , Dinoprost/analogs & derivatives , Dinoprost/urine , Female , Humans , Lipid Peroxidation , Lymphocytes/metabolism , Male , Malondialdehyde/analysis , Middle Aged , Oxidation-Reduction , Reactive Oxygen Species/metabolism , Tyrosine/analogs & derivatives , Tyrosine/analysis , Young Adult
20.
J Agric Food Chem ; 58(13): 7510-9, 2010 Jul 14.
Article in English | MEDLINE | ID: mdl-20527950

ABSTRACT

Two multiresidue methods based on different extraction procedures have been developed and compared for the liquid chromatography electrospray ionization tandem mass spectrometry analysis of 17 mycotoxins including ochratoxin A, aflatoxins (B(1), B(2), G(1), and G(2)), zearalenone, fumonisins (B(1) and B(2)), T-2 toxin, HT-2 toxin, nivalenol, deoxynivalenol, 3- and 15-acetyldeoxynivalenol, fusarenon-X, diacetoxyscirpenol, and neosolaniol in cereal-based commodities. The extraction procedures considered were a QuEChERS-like method and one using accelerated solvent extraction (ASE). Both extraction procedures gave similar performances in terms of linearity (r(2) > 0.98) and precision (both RSD(r) and RSD(iR) < 20%). Trueness was evaluated through participation in four proficiency tests and by the analysis of two certified reference materials and one quality control material. Satisfactory Z scores (|Z| < 2) and trueness values (73-130%) were obtained by the proposed procedures. Limits of quantification were similar by both methods and were within the 1.0-2.0 microg/kg range for aflatoxins, 0.5 microg/kg for ochratoxin A, and the 5-100 microg/kg range for all other mycotoxins tested. The QuEChERS-like method was found to be easier to handle and allowed a higher sample throughput as compared to the ASE method.


Subject(s)
Chromatography, Liquid/methods , Edible Grain/chemistry , Food Contamination/analysis , Mycotoxins/analysis , Spectrometry, Mass, Electrospray Ionization/methods , Sensitivity and Specificity
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