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A fast and simple analytical method was developed and characterized for the determination of aflatoxins (B 1 , B 2 , G 1 and G 2 ) in rice. The procedure is based on a simple solid-liquid extraction without further clean-up, and analysis by ultra-high performance liquid chromatography coupled with fluorescence detection. Fluorescence emission of aflatoxins B 1 and G 1 was enhanced by post-column chemical derivatization using pyridinium bromide perbromide. The analytical method was satisfactorily characterized in white and brown rice. Under optimum conditions, external calibration in solvent could be used for quantification purposes and limits of quantification were below the maximum contents established by the European Union regulation for these contaminants/commodity group combination (0.07-0.14 µg/kg for white rice and 0.20-0.28 µg/kg for brown rice). Recovery studies carried out at three different concentration levels (0.5, 2 and 5 µg/kg) showed values in the range of 84.5-105.3%, and RSDs ≤ 5%., (Copyright © 2017 Elsevier Ltd. 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.)

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.)

This paper presents two sample treatments, dispersive liquid-liquid microextraction (DLLME) and QuEChERS for the determination of 9 sulfonamides, regulated by the EU Council in milk samples. Both methods represent useful alternatives to conventional procedures based mainly in solid-phase extraction, in terms of simplicity, reduction of organic solvents, sample throughput and effectiveness for cleaning-up complex samples. They have been evaluated and compared in terms of efficiency, trueness, sensitivity and precision, using HPLC with fluorescence detection employing a previous derivatisation step with fluorescamine. Clean extracts were obtained with recoveries between 90.8-104.7% and 83.6-104.8% for DLLME and QuEChERS, respectively. Matrix-matched calibration curves were established for both methods using milk samples spiked at four concentration levels. LODs (3xS/N) lower than 1.21μgL(-)(1) and 2.73μgL(-)(1) for DLLME and QuEChERS, respectively, were obtained in all cases. The precision, in terms of repeatability and intermediate precision, was lower than 10% in all cases., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

A method based on reverse phase capillary high performance liquid chromatography (capillary HPLC) coupled to laser-induced fluorescence detection (LIF) has been proposed for the determination of ochratoxin A (OTA) in wine samples. An anionic micellar medium was added to the mobile phase for increasing the fluorescence intensity and peak efficiency. Dispersive liquid-liquid microextraction (DLLME) has been used as a simple and efficient sample pretreatment method for the analysis of OTA in wines, being optimised by means of experimental design. The limit of detection was 5.5 ng L(-1) (3 × S/N) and recoveries for different wines ranged from 91.7 to 98.1%. The proposed methodology could be classified as a green analytical chemistry alternative, combining the low organic solvent volumes required in the DLLME with the reduced consumption of mobile phase in capillary HPLC. The use of LIF as detector provided an extremely sensitive method for the determination of OTA in wines., (Copyright © 2012 Elsevier Ltd. All rights reserved.)