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Poultry farming has developed into one of Algeria's most productive industrial farming because of the growing demand for sources of protein among Algerian society. Laying hen feed consists mainly of cereals, which can be contaminated with molds and subsequently with their secondary metabolites known as mycotoxins. These later can pose a serious danger to the production and quality of eggs in the commercial layer industry. This work focuses on the detection of emerging mycotoxins, mainly enniatins (ENNs) and beauvericin (BEA), in poultry feed and eggs from different locations in Algeria. Two different QuEChERS-based extractions were established to extract ENNs and BEA from chicken feed and eggs. The determination of mycotoxin occurrence was achieved by a UHPLC-MS/MS method using 0.1% (v/v) formic acid in water and MeOH as mobile phase, an ESI interface operating in positive mode, and a triple quadrupole mass spectrometer operating in MRM for the detection. Matrix-matched calibration curves were carried out for both matrices, obtaining good linearity (R 2  > 0.99). The method performance was assessed in terms of extraction recovery (from 87 to 107%), matrix effect (from - 47 to - 86%), precision (RSD < 15%), and limits of quantitation (≤ 1.1 µg/kg for feed and ≤ 0.8 µg/kg for eggs). The analysis of 10 chicken feed samples and 35 egg samples composed of a 10-egg pool each showed that ENN B 1 was the most common mycotoxin (i.e., found in 9 feed samples) with contamination levels ranging from 3.6 to 41.5 µg/kg, while BEA was detected only in one feed sample (12 µg/kg). However, eggs were not found to be contaminated with any mycotoxin at the detection limit levels. Our findings indicate that the searched mycotoxins are present in traces in feed and absent in eggs. This can be explained by the application of a mycotoxin binder. However, this does not put a stop on the conduction of additional research and ultimately setting regulations to prevent the occurrence of emerging mycotoxins., (© 2024. The Author(s).)

The on-line coupling of micellar electrokinetic chromatography and mass spectrometry (MEKC-MS) is often hampered by incompatibility problems leading to reduced separation performance and unfavorable limits of detection (LODs). Here we propose a new selective and highly sensitive MEKC-MS/MS method employing a sheathless porous-tip interface in combination with a micellar phase comprised of semi-volatile surfactant molecules. Carbamate pesticides (CRBs) were selected as representative model compounds being neutral toxic pollutants potentially present at trace levels in environmental water samples. A background electrolyte of 75mM perfluorooctanoic acid adjusted to pH 9.0 with ammonium hydroxide allowed efficient separation of 15 CRBs and appeared fully compatible with electrospray ionization (ESI)-MS. Interfacing parameters, such as the distance between the capillary tip and mass-spectrometer inlet, ESI voltage, and dry gas temperature and flow were optimized in order to attain good spray stability and high analyte signal-to-noise ratios. For CRBs the LODs ranged from 0.2 to 3.9ngL -1 (13nL injected, i.e., 2% of capillary volume), representing an improvement for certain CRBs of more than 300-fold when compared with conventional sheath-liquid interfacing. Good linearity (R 2 >0.99) and satisfactory reproducibility were obtained for all CRBs with interday RSD values for peak area and migration time of 4.0-11.3% and below 1.5%, respectively. Analysis of spiked mineral water showed that the new MEKC-MS/MS method allows selective and quantitative determination of CRB concentrations below the maximum residue limit of 100ngL -1 without the need for sample preconcentration., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Vegetable milks are considered as functional foods due to their physiological benefits. Although the consumption of these products has significantly increased, they have received little attention in legislation with regard to contaminants. However, they may contain mycotoxins resulting from the use of contaminated raw materials. In this work, ultra-high-performance liquid chromatography tandem mass spectrometry has been proposed for the determination of the most relevant Fusarium toxins (fumonisin B 1 and B 2 , HT-2 and T-2 toxins, zearalenone, deoxynivalenol and fusarenon-X) in different functional beverages based on cereals, legumes and seeds. Sample treatment consisted of a simple salting-out-assisted liquid-liquid extraction with no further clean-up. The method provided limits of quantification between 3.2 and 57.7 µg L -1 , recoveries above 80% and precision with RSD lower than 12%. The method was also applied for studying the occurrence of these mycotoxins in market samples of vegetable functional beverages and deoxynivalenol was found in three oat-based commercial drinks.

A selective and rapid method has been developed to determine 15 antibiotic residues (eight tetracyclines and seven quinolones) in milk samples by capillary zone electrophoresis coupled with quadrupole time-of-flight mass spectrometry (CZE-Q-TOF-MS). The use of this hybrid mass spectrometer allowed obtaining full scan and full MS/MS spectra for quantification/confirmation purposes in a single run. In addition, solid phase extraction (SPE) using the new Oasis PRiME HLB cartridge was proposed for the extraction, achieving excellent results in terms of sample throughput. The proposed method was validated using whole cow milk as representative matrix. Good linearity was obtained (R 2 >0.99) for all the studied compounds. The precision, expressed as relative standard deviation (%, RSD), at two concentration levels (50 and 100μgkg -1 ) was below 13%. Recoveries obtained from goat milk, whole cow milk and semi-skimmed cow milk, at two concentration levels, ranged from 76 to 106%, while limits of quantification ranged from 1.5 to 9.6μgkg -1 , being lower than the established maximum residue limits in the European legislation. Matrix effect was negligible in all cases, showing that with this new SPE sorbent cleanest extracts were obtained with a minimum number of steps in the sample treatment. Thus, the proposed SPE-CZE-Q-TOF-MS method is suitable for multiclass multiresidue monitoring in different types of milk samples., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A new reliable, fast and highly sensitive method based on ultra-high performance liquid chromatography tandem mass spectrometry has been developed and validated for the determination of 28 carbamates in aromatic herbs. A modified QuEChERS-based method was optimized for the extraction of carbamate residues from a wide variety of fresh herbal products. The proposed method allowed recoveries higher than 72%, achieving quantification limits of 2μgkg(-1), therefore below maximum residue limits established for this type of samples. The combination of QuEChERS with UHPLC-MS/MS introduces a high-throughput methodology for the monitoring of these residues in this type of matrices scarcely explored. The analysis of the real samples revealed that several samples sold in the European Union and in the North West region of Cameroon contain pesticides in concentrations below the maximum residue limits., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

A simple and efficient method for the determination of 28 carbamates in high-fat cheeses is proposed. The methodology is based on a modified quick, easy, cheap, effective, rugged, and safe procedure as sample treatment using a new sorbent (Z-Sep + ) followed by ultra-high performance liquid chromatography with tandem mass spectrometry determination. The method has been validated in different kinds of cheese (Gorgonzola, Roquefort, and Camembert), achieving recoveries of 70-115%, relative standard deviations lower than 13% and limits of quantification lower than 5.4 μg/kg, below the maximum residue levels tolerated for these compounds by the European legislation. The matrix effect was lower than ±30% for all the studied pesticides. The combination of ultra-high performance liquid chromatography and tandem mass spectrometry with this modified quick, easy, cheap, effective, rugged, and safe procedure using Z-Sep + allowed a high sample throughput and an efficient cleaning of extracts for the control of these residues in cheeses with a high fat content., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) with electrospray ionization has been proposed for the determination of fifteen natural destruxins (A, B, C, D, E, Ed, Ed1, A2, B2, D2, E2, Cl, DesmA, DesmB, and DH-A), secondary metabolites with insecticidal and phytotoxic activities produced by Metarhizium species fungus, which are being studied as biological agents in pest control. Therefore, procedures to control them in the food chain are required, starting with crops. As a consequence, in this study, a simple QuEChERS-based destruxin (dtx) extraction procedure has been developed and validated in four different parts of potato plant (tuber, root, stem and leaves) for the first time. For dtx A, the limits of detection obtained, ranged between 0.5 and 1.3 μg/kg, and for quantification, ranged between 1.7 and 4.2 μg/kg. Precision values were below 8.5%; and in all cases, recoveries were higher than 91%. Finally, the method has been applied in potato samples inoculated by EAMa 01/58-Su strain, where dtxs A and B were detected and quantified. In all cases, dtx B concentration was higher than dtx A., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A new analytical method based on capillary zone electrophoresis-tandem mass spectrometry is proposed and validated for the identification and simultaneous quantification of nine aminoglycosides in honey samples. Detection using an ion trap mass analyzer operating in the multiple reaction monitoring mode was used. Different parameters were optimized in order to obtain an adequate separation combined with the highest sensitivity. In order to achieve high selectivity in the sample treatment, a commercially-available molecularly imprinted polymer has been used for the solid phase extraction of the analytes. Under optimum conditions, recoveries for fortified samples ranged from 88.2 to 99.8%, with relative standard deviations lower than 8%. The limits of detection ranged from 0.4 to 28.5 μg kg(-1). Furthermore, the decision limit and the detection capability were evaluated, ranging from 3.5 to 60.5 μg kg(-1) and from 6.0 to 103.1 μg kg(-1), respectively, demonstrating the sensitivity and applicability of this fast and simple method., (Copyright © 2015 Elsevier B.V. All rights reserved.)

A new method based on vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction has been developed for the extraction of carbamate pesticides in juice samples prior to their determination by micellar electrokinetic chromatography coupled to tandem mass spectrometry. This sample treatment allowed the satisfactory extraction and the extract clean-up of 25 carbamates from different fruit and vegetal juices (banana, tomato, and peach). In this study, the addition of ammonium perfluorooctanoate in the aqueous sample in combination with vortex agitation, provided very clean extracts with short extraction times. Under optimized conditions, recoveries of the proposed method for these pesticides from fortified juice samples ranged from 81% to 104%, with relative standard deviations lower than 15%. Limits of quantification were between 2.3µgkg(-)(1) and 4.7µgkg(-)(1), showing the high sensitivity of this fast and simple method., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Consumption of cereal syrups is increasing nowadays. Mycotoxins may be found in syrups resulting from the use of contaminated raw material or invading microorganisms in the final manufactured product. However, these matrices have been scarcely explored regarding their mycotoxin content. A sensitive, simple and rapid method for the determination of ten mycotoxins (ochratoxin A, fumonisin B1, fumonisin B2, deoxynivalenol, fusarenon-X, T-2 and HT-2 toxin, citrinin, sterigmatocystin and zearalenone) in cereal syrups (rice, wheat and barley) has been developed and characterised using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) and a sample treatment based on QuEChERS procedure. Matrix-matched calibration curves were established and limits of quantification were below the limits usually established by current legislation in different foodstuff. The relative standard deviation of the whole analytical method was lower than 12% in all cases, while recoveries ranged from 70.2% to 100.6%, therefore fulfilling the current requirements for mycotoxins analysis., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In this study a fast, selective and sensitive multiresidue method based on QuEChERS methodology has been evaluated and validated for the determination of carbamate pesticides, in edible vegetable oils by UHPLC-MS/MS. A new clean-up sorbent, Supel(TM) QuE Z-Sep(+), has been successfully applied in vegetable oil extracts. Z-Sep(+) was compared with other sorbents (i.e. mixture of C18 and PSA) previously used for dispersive solid phase extraction of these matrices, reducing more effectively matrix effects without a significant decrease of analyte recoveries. Matrix effect was studied in different matrices (extra-virgin olive, sunflower, maize, linseed and sesame oil) being ≤│30│% for most of the studied pesticides. Under optimum conditions, recoveries ranged from 74% to 101%, with relative standard deviations lower than 10%. Limits of quantification ranged from 0.09 to 2.0 µg kg(-1), allowing their determination at the low concentration levels demanding by current legislation., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In this work molecularly imprinted polymers have been evaluated as sorbent for the construction of an in-line solid phase extraction analyte concentrator in capillary electrophoresis coupled with mass spectrometry for the determination of the eight regulated veterinary quinolones in bovine milk samples. Different parameters affecting the analyte concentrator performance, such as sample pH, volume and composition of the elution plug and injection time, were studied. Sample volumes of 22μL (2bar for 15min) were loaded on the MISPE microcartridge and the retained analytes were eluted by injecting a plug of MeOH/H2O/NH3 (60/37/3 by volume) for 125s at 50mbar (60nL). The proposed method is simple for the monitoring of these antibiotic residues in milk samples, allowing the direct injection of the samples with minimum sample pretreatment, achieving limits of detection between 3.8 and 4.7μgkg(-1) and unequivocal identification of the compounds working in tandem mass spectrometry. Recoveries ranging from 70.0 to 102.3% were obtained and satisfactory intra-day and inter-day RSDs were achieved (≤12% and 15% respectively). Reproducibility among different constructed analyte concentrators showed RSD≤11%., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A new sensitive multiresidue method based on ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) has been developed for the detection, confirmation and quantification of twenty five carbamates in wine samples. The separation was achieved in 5.5 min, using a Zorbax Eclipse plus RRHD C18 column (50 mm×2.1 mm, 1.8 μm), with a mobile phase of water and methanol, both of them with 0.01% formic acid. The analytes were detected in positive mode with multiple reaction monitoring mode. Ultrasound-assisted surfactant-enhanced emulsification microextraction (UASEME), using a low-density extraction solvent has been optimized for the satisfactory extraction of carbamates and clean-up of extracts. The matrix effect was studied, showing that the proposed procedure provides very clean extracts. Under optimum conditions, recoveries for fortified wine samples ranged from 74 to 102%, with relative standard deviations lower than 6%. Limits of quantification ranged from 0.15 to 0.92 μgl(-1), showing the high sensitivity of this fast and simple method and its compliance with current requirements., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) has been proposed for the determination of 15 mycotoxins in milk thistle (Silybum marianum), including aflatoxins, fumonisins, trichothecenes, ochratoxin A, citrinin, sterigmatocystin and zearalenone. The mycotoxins were detected by electrospray ionization in positive ion mode and multiple reaction monitoring (MRM), achieving the separation in about 4min. Sample treatment consisted of a modified method based on a first step using a QuEChERS-based procedure which allowed the determination of fumonisin B1, fumonisin B2, nivalenol, deoxynivalenol and fusarenon-X, and a subsequent clean-up based on dispersive liquid-liquid microextraction (DLLME) for the determination of the rest of mycotoxins. The method has been validated in extract and seeds of milk thistle, obtaining limits of quantification lower than those usually permitted by legislation in food matrices, with precisions lower than 10%. Recoveries were between 62.3% and 98.9%, except for zearalenone in seeds samples and citrinin in extract. The method was also applied for studying the occurrence of these mycotoxins in market samples (six samples of seeds, three of them purchased in bulk in a street vendor, and one natural extract of milk thistle), and HT-2, T-2 and zearalenone have been found in some of the samples. To the best of our knowledge, this is the first time that this type of treatment has been used for these complex food matrices, allowing the analyses of the most important mycotoxins., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A reliable and rapid ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method has been developed for the determination of the eight quinolones of veterinary use regulated by European Union (marbofloxacin, ciprofloxacin, danofloxacin, enrofloxacin, sarafloxacin, difloxacin, flumequine and oxolinic acid). Chromatographic conditions were optimized in order to increase sample throughput and sensitivity. The antibiotics were detected by electrospray ionization in positive ion mode with multiple reaction monitoring (MRM) and MS/MS conditions were optimized in order to increase selectivity, selecting the corresponding product ions for quantification and identification. The separation was achieved in 3 min, using a Zorbax Eclipse Plus C18 column (50 mm × 2.1mm, 1.8 μm), with a mobile phase of 0.02% aqueous formic acid solution and acetonitrile. A dispersive solid phase extraction methodology, often referred to as the "QuEChERS" (quick, easy, cheap, effective, rugged, and safe) method, was optimized for extraction of the quinolones from honey and also it was evaluated for other bee products such as royal jelly and propolis. The method was validated for each matrix in terms of linearity, trueness, precision, limits of detection (LODs) and quantification (LOQ). LODs ranged between 0.2 and 4.1 μg kg(-1) with precision lower than 12% and satisfactory recoveries in most cases. The method was also applied for studying the occurrence of these antibiotics in several market samples., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A new analytical method based on CZE coupled with tandem MS detection (CE-MS/MS) has been developed for the simultaneous determination of nine penicillins of human and veterinary use (nafcillin, dicloxacillin, cloxacillin, oxacillin, ampicillin, penicillin G, amoxicillin, penicillin V and piperacillin), whose levels are regulated by the EU Council regulation No. 2377/90 in animal edible tissues. CE separation conditions, sheath liquid composition and electrospray parameters have been carefully optimized to reach high sensitivity and precision. Separation was carried out in a 96 cm total length fused-silica capillary (50 microm id, 360 microm od) using 60 mM ammonium acetate at pH 6.0 as running buffer. Lomefloxacin was used as internal standard. MS/MS experiments were carried out using an IT as analyzer operating in multiple reaction monitoring mode to achieve the minimum number of identification points established by the 2002/657/EC European Decision. The use of an SPE procedure in two steps, combining Oasis hydrophilic-liphophilic balance and Alumina N cartridges provide a satisfactory preconcentration and clean up treatment for meat samples after extraction of the compounds with ACN. Only Oasis hydrophilic-liphophilic balance cartridges were necessary in water samples to obtain adequate recoveries. The method has been characterized for its use in meat and water samples, using matrix-matched calibrations. For chicken muscle samples, LODs between 8 and 12 microg/kg have been obtained, in all cases lower than the maximum residue limits permitted. For water samples LODs from 0.18 to 0.26 microg/L could ensure its satisfactory application in aquatic samples.