Determination of multiclass cyanotoxins in blue-green algae (BGA) dietary supplements using hydrophilic interaction liquid chromatography-tandem mass spectrometry.

In recent years, the consumption of blue-green algae (BGA) dietary supplements is increasing because of their health benefits. However, cyanobacteria can produce cyanotoxins, which present serious health risks. In this work we propose hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry (HILIC-MS/MS) to determine cyanotoxins in BGA dietary supplements. Target toxins, including microcystin-leucine-arginine (MC-LR) and microcystin-arginine-arginine (MC-RR), nodularin, anatoxin-a and three non-protein amino acids, β-N-methylamino-L-alanine (BMAA), 2,4-diaminobutyric acid (DAB) and N-(2-aminoethyl)glycine (AEG), were separated using a SeQuant ZIC-HILIC column. Cyanotoxin extraction was based on solid–liquid extraction (SLE) followed by a tandem-solid phase extraction (SPE) procedure using Strata-X and mixed-mode cation-exchange (MCX) cartridges. The method was validated for BGA dietary supplements obtaining quantification limits from 60 to 300 µg·kg−1. Nine different commercial supplements were analyzed, and DAB, AEG, and MCs were found in some samples, highlighting the relevance of monitoring these substances as precaution measures for the safe consumption of these products.

Posted in B-AGR-202-UGR20, Blue-green algae, Cyanotoxins, HILIC, Mass spectrometry, RTI2018-097043-B-I00, SPE | Tagged , , | Comments Off on Determination of multiclass cyanotoxins in blue-green algae (BGA) dietary supplements using hydrophilic interaction liquid chromatography-tandem mass spectrometry.

Ion mobility-mass spectrometry to extend analytical performance in the determination of ergot alkaloids in cereal samples.

This work evaluates the potential of ion mobility spectrometry (IMS) to improve the analytical performance of current liquid chromatography-mass spectrometry (LC-MS) workflows applied to the determination of ergot alkaloids (EAs) in cereal samples. Collision cross section (CCS) values for EA epimers are reported for the first time to contribute to their unambiguous identification. Additionally, CCS values have been inter-laboratory cross-validated and compared with CCS values predicted by machine-learning models. Slight differences were observed in terms of CCS values for ergotamine, ergosine and ergocristine and their corresponding epimers (from 3.3 to 4%), being sufficient to achieve a satisfactory peak-to-peak resolution for their unequivocal identification. A LC-travelling wave ion mobility (TWIM)-MS method has been developed for the analysis of EAs in barley and wheat samples. Signal-to-noise ratio (S/N) was improved between 2.5 and 4-fold compared to the analog LC-TOF-MS method. The quality of the extracted ion chromatograms was also improved by using IMS.

Posted in Barley, Ergot alkaloids, Ion mobility, PID2021-127804OB-I00, QuEChERS, UHPLC, Wheat | Tagged , , | Comments Off on Ion mobility-mass spectrometry to extend analytical performance in the determination of ergot alkaloids in cereal samples.

Non-aqueous capillary electrophoresis–time of flight mass spectrometry method to determine emerging mycotoxins.

Enniatins (ENN) and beauvericin (BEA) are emerging mycotoxins that have been traditionally determined by liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS). However, to the best of our knowledge, no analytical methods based on capillary electrophoresis (CE)–MS/MS have been reported so far. Due to their non-polar nature, in this work, a non-aqueous CE (NACE) method coupled to quadrupole time-of-flight–MS is proposed for the first time to identify and quantify these mycotoxins. Determination was achieved in 4 min under optimum conditions: 40 mM ammonium acetate in 80:20 (v/v) acetonitrile-methanol (buffer), 30 kV (voltage), 80 cm (capillary length), 20 °C (capillary temperature) and 50 mbar × 30 s (injection). Higher selectivity can be achieved when compared with LC due to the formation of exclusive CE adducts such as [M + CH3CH2NH3]+. “All Ions” acquisition mode was selected as it allows the quantification of the usual ENNs, as well as the identity confirmation of less common ENNs.

The method was validated for wheat samples, obtaining limits of quantification from 4.0 to 8.3 μg/kg depending on the emerging mycotoxin, recovery values higher than 87.4%, and intra- and inter-day precision values (RSDs) lower than 15.1% in all cases. Finally, 29 wheat samples were analyzed, finding 26 samples with concentrations of enniatin B higher than the limit of quantification (7.5–1480 μg/kg), 20 for enniatin B1 (5.2–550 μg/kg), 7 for enniatin A (10–55 μg/kg), 4 for enniatin A1 (12.6–77 μg/kg) and 5 for BEA (9.2–16.4 μg/kg). Moreover, two other ENNs were tentatively identified.

Posted in B-AGR-202-UGR20, EQC2018-004453-P, Enniatins, Mass spectrometry, Mycotoxins, NACE, RTI2018-097043-B-I00, SALLE, Wheat | Tagged , , | Comments Off on Non-aqueous capillary electrophoresis–time of flight mass spectrometry method to determine emerging mycotoxins.

Sweeping-micellar electrokinetic chromatography with tandem mass spectrometry as an alternative methodology to determine neonicotinoid and boscalid residues in pollen and honeybee samples.

In this work, it is proposed for the first time an electrophoretic approach based on micellar electrokinetic chromatography coupled with tandem mass spectrometry (MEKC-MS/MS) for the simultaneous determination of nine neonicotinoids (NNIs) together with the fungicide boscalid in pollen and honeybee samples. The separation was performed using ammonium perfluorooctanoate (50 mM, pH 9) as both volatile surfactant and electrophoretic buffer compatible with MS detection. A stacking strategy for accomplishing the on-line pre-concentration of the target compounds, known as sweeping, was carried out in order to improve separation efficiency and sensitivity. Furthermore, a scaled-down QuEChERS was developed as sample treatment, involving a lower organic solvent consumption and using Z-Sep+ as dispersive sorbent in the clean-up step. Regarding the detection mode, a triple quadrupole mass spectrometer was operating in positive ion electrospray mode (ESI+) under multiple reaction monitoring (MRM). The main parameters affecting MS/MS detection as well as the composition of the sheath-liquid (ethanol/ultrapure water/formic acid, 50:49.5:0.5 v/v/v) and other electrospray variables were optimized in order to achieve satisfactory sensitivity and repeatability. Procedural calibration curves were established in pollen and honeybee samples with LOQs below 11.6 µg kg−1 and 12.5 µg kg−1, respectively. Precision, expressed as RSD, lower than 15.2% and recoveries higher than 70% were obtained in both samples. Two positive samples of pollen were found, containing imidacloprid and thiamethoxam. Imidacloprid was also found in a sample of honeybees. The obtained results highlight the applicability of the proposed method, being an environmentally friendly, efficient, sensitive and useful alternative for the determination of NNIs and boscalid in pollen and honeybee samples.

Posted in B-AGR-202-UGR20, EQC2018-004453-P, Honeybees, Insects, MEKC, Mass spectrometry, Neonicotinoids, Pesticides, Pollen, QuEChERS, RED2018-102522-T, RTI2018-097043-B-I00, Sweeping | Tagged , , , | Comments Off on Sweeping-micellar electrokinetic chromatography with tandem mass spectrometry as an alternative methodology to determine neonicotinoid and boscalid residues in pollen and honeybee samples.

Multiclass cyanotoxin analysis in reservoir waters: Tandem solid-phase extraction followed by zwitterionic hydrophilic interaction liquid chromatography-mass spectrometry.

The presence of cyanobacteria and cyanotoxins in all water bodies, including ocean water and fresh water sources, represents a risk for human health as eutrophication and climate change are enhancing their level of proliferation. For risk assessment and studies on occurrence, the development of reliable and sensitive analytical approaches able to cover a wide range of cyanotoxins is essential. This work describes the development of an HILIC-MS/MS multiclass method for the simultaneous analysis of eight cyanotoxins in reservoir water samples belonging to three different classes according to their chemical structure: cyclic peptides (microcystin-LR, microcystin-RR and nodularin), alkaloids (cylindrospermopsin, anatoxin-a) and three non-protein amino acids isomers such as β-methylamino-L-alanine, 2,4-diaminobutyric acid and N-(2-aminoethyl)glycine). A SeQuant ZIC-HILIC column was employed to achieve the chromatographic separation in less than 12 min. Previously, a novel sample treatment based on a tandem solid-phase extraction (SPE) system using mixed cation exchange (MCX) and Strata-X cartridges was investigated with the aim of extracting and preconcentrating this chemically diverse group of cyanotoxins. The Strata-X cartridge, which was configured first in the line of sample flow, retained the low polar compounds and the MCX cartridge, which was at the bottom of the dual system, retained mainly the non-protein amino acids. The optimization procedure highlighted the importance of sample ion content for the recoveries of some analytes such as the isomers β-N-methylamino-L-alanine and 2-4-diaminobutyric acid. Method validation was carried out in terms of linearity, limit of detection (LOD) and quantification (LOQ), recoveries, matrix effect and precision in terms of repeatability and intermediate precision. This work represents the first analytical method for the simultaneous analysis of these multiclass cyanotoxins in reservoir water samples, achieving LOQs in the very low range of 7·10−3 – 0.1 μg L−1. Despite high recoveries obtained at the LOQ concentration levels (101.0–70.9%), relative standard deviations lower than 17.5% were achieved.

Posted in Cyanotoxins, HILIC, Mass spectrometry, RTI2018-097043-B-I00, SPE, Water | Tagged , , | Comments Off on Multiclass cyanotoxin analysis in reservoir waters: Tandem solid-phase extraction followed by zwitterionic hydrophilic interaction liquid chromatography-mass spectrometry.

A natural deep eutectic solvent as a novel dispersive solvent in dispersive liquid-liquid microextraction based on solidification of floating organic droplet for the determination of pesticide residues.

Current trends in analytical chemistry encourage the use of innocuous solvents to develop modern methods aligned with green chemistry. In this sense, natural deep eutectic solvents (NADESs) have emerged as a novel generation of green solvents which can be employed in sample treatments as an alternative to the toxic organic solvents commonly used so far. In this work, a new extraction method employs dispersive liquid-liquid microextraction based on a solid floating organic droplet (DLLME-SFO), by using a mixture composed of a less dense than water extraction solvent, 1-dodecanol, and a novel dispersive solvent, NADES. The methodology was proposed to extract and preconcentrate some pesticide residues (fipronil, fipronil-sulfide, fipronil-sulfone, and boscalid) from environmental water and white wine samples before analysis by liquid-chromatography coupled to ultraviolet detection (HPLC-UV). Limits of quantification (LOQs) lower than 4.5 μg L−1, recoveries above 80%, and precision, expressed as RSD, below 15% were achieved in both samples showing that the proposed method is a powerful, efficient, and green alternative for the determination of these compounds and, therefore, demonstrating a new application for NADES in sample preparation. In addition, the DLLME-SFOD-HPLC-UV method was evaluated and compared with other reported approaches using the Analytical GREEnness metric approach, which highlighted the greenness of the proposed method.

Posted in Fipronil, HPLC, NADES, RED2018-102522-T, UV-vis, Water, Wine | Tagged , | Comments Off on A natural deep eutectic solvent as a novel dispersive solvent in dispersive liquid-liquid microextraction based on solidification of floating organic droplet for the determination of pesticide residues.

Determination of principal ergot alkaloids in swine feeding

Ergot alkaloids are secondary metabolites produced by fungi in the genus Claviceps. They contaminate a large variety of cereals, such as rye, triticale, wheat and barley. The ingestion of contaminated cereals might cause adverse health effects in humans and animals. In fact, pigs, cattle, sheep, and poultry are involved in sporadic outbreaks and, although there are several studies about occurrence of ergot alkaloids in grain cereals, there are scarce studies focused on compound feed. Twelve ergot alkaloids have been quantified in 228 feed samples intended for swine. The analytes were extracted using QuEChERS with Z-Sep+ as sorbent in the clean-up step, which reduced the matrix effect, allowing limits of quantification between 2.1 and 21.7 μg kg–1. The analytes were subsequently quantified by ultra-high-performance liquid chromatography with tandem mass spectrometry (UHPLC–MS/MS). A total of 29 samples (12.7%) revealed contamination by at least one ergot alkaloid, and among contaminated samples, 65% were contaminated by more than one. Only 6 of 12 target ergot alkaloids showed concentrations above the limit of quantification. The concentrations for individual ergot alkaloids ranged between 5.9 μg kg–1 for ergosinine to 145.3 μg kg–1 for ergometrine (the predominant ergot alkaloid), while the total ergot alkaloid content ranged from 5.9 to 158.7 μg kg–1. The occurrence of ergot alkaloids in feed samples in Spain seems to be lower than in other regions of Europe. All the samples fulfilled current recommendations of the feed industry about practical limits for ergot alkaloids in pig feeds. This suggests that the feeds are safe for pig consumption, regarding the presence of ergot alkaloids.

Posted in Animal feed, Ergot alkaloids, Mass spectrometry, QuEChERS, RTI2018-097043-B-I00, UHPLC | Tagged , , | Comments Off on Determination of principal ergot alkaloids in swine feeding

Simple and efficient method for the determination of fipronil and two main metabolites in eggs by capillary liquid chromatography.

Capillary liquid chromatography (CLC) with UV-diode array detection has been proposed for the first time to determine fipronil and two metabolites, fipronil-sulfide and fipronil-sulfone in hen egg samples. Under optimum conditions, analytes eluted in less than 12 min. Despite the complexity of egg samples, a simple and fast sample preparation method based on salting-out assisted liquid–liquid extraction (SALLE) was developed using acetonitrile as extraction solvent and ammonium sulfate as salting out reagent. To obtain satisfactory extraction efficiencies for the target compounds, several parameters affecting the procedure were optimized, including the nature and amount of the extraction solvent and the type and amount of salting-out reagent, among others. Validation parameters of the proposed SALLE-CLC-UV method yielded satisfactory results with repeatability and intermediate precision, expressed as relative standard deviation (RSD), below 9% and 11%, respectively and recoveries above 80%. Good linearity was obtained (R2 > 0.990) with limits of detection (LOD) below 5 μg·kg−1. The advantages of a miniaturized technique such as CLC in terms of reduced sample and solvent consumption, combined with simplicity of the SALLE procedure, make this method an attractive green alternative to traditional LC for the monitoring of these residues in egg samples.

Posted in Capillary HPLC, Eggs, Fipronil, Pesticides, RTI2018-097043-B-I00, SALLE, UV-vis | Tagged , , | Comments Off on Simple and efficient method for the determination of fipronil and two main metabolites in eggs by capillary liquid chromatography.

Determination of the main ergot alkaloids and their epimers in oat-based functional foods by ultra-high performance liquid chromatography tandem mass spectrometry.

An ultra-high performance liquid chromatography coupled to tandem mass spectrometry method is proposed for the determination of the major ergot alkaloids (ergometrine, ergosine, ergotamine, ergocornine, ergokryptine, ergocristine) and their epimers (ergometrinine, ergosinine, ergotaminine, ergocorninine, ergokryptinine, and ergocristinine) in oat-based foods and food supplements. A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure was applied as sample treatment, reducing the consumption of organic solvent and increasing sensitivity. This method involved an extraction with acetonitrile and ammonium carbonate (85:15, v/v) and a clean-up step based on dispersive solid-phase extraction, employing a mixture of C18/Z-Sep+ as sorbents. Procedural calibration curves were established and limits of quantification were below 3.2 μg/kg for the studied compounds. Repeatability and intermediate precision (expressed as RSD%) were lower than 6.3% and 15%, respectively, with recoveries ranging between 89.7% and 109%. The method was applied to oat-based products (bran, flakes, flour, grass, hydroalcoholic extracts, juices, and tablets), finding a positive sample of oat bran contaminated with ergometrine, ergosine, ergometrinine, and ergosinine (total content of 10.7 μg/kg).

Posted in Ergot alkaloids, Mass spectrometry, Mycotoxins, Oat, QuEChERS, RTI2018-097043-B-I00, UHPLC | Tagged , , | Comments Off on Determination of the main ergot alkaloids and their epimers in oat-based functional foods by ultra-high performance liquid chromatography tandem mass spectrometry.

Occurrence of ergot alkaloids in barley and wheat from Algeria

The natural occurrence of six major ergot alkaloids, ergometrine, ergosine, ergotamine, ergocornine, ergokryptine and ergocristine, as well as their corresponding epimers, were investigated in 60 cereal samples (barley and wheat) from Algeria. Ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) and a QuEChERS extraction method were used for sample analysis. The results revealed that 12 out of 60 samples (20%) were contaminated with ergot alkaloids. Wheat was the most contaminated matrix, with an incidence of 26.7% (8 out of 30 samples). The concentration of total ergot alkaloids ranged from 17.8 to 53.9 μg/kg for barley and from 3.66 to 76.0 μg/kg for wheat samples. Ergosine, ergokryptine and ergocristine showed the highest incidences in wheat, while ergometrine was the most common ergot in barley.

Posted in Barley, Ergot alkaloids, Mass spectrometry, Mycotoxins, QuEChERS, RTI2018-097043-B-I00, UHPLC, Wheat | Tagged , , | Comments Off on Occurrence of ergot alkaloids in barley and wheat from Algeria