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To ensure the success of large-scale sporting events, prevent the contamination of food by prohibited substances, and evaluate the risk of foodborne stimulants and other hormones in food, it is necessary to establish a high-throughput, rapid, and accurate detection method for foodborne stimulants and other hormones. In this study, a QuEChERS method is proposed for the simultaneous determination of 44 foodborne stimulants and 6 progestogens using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The analyzed foodborne stimulants include 19

An automatic multi-plug filtration cleanup (m-PFC) tip-filtration method was developed to reduce the manual operation workload in sample preparation. In this work, m-PFC was based on multi-walled carbon nanotubes mixed with primary secondary amines and anhydrous magnesium sulfate (MgSO4) in a packed column for analysis of pesticide residues followed by ultra-performance liquid chromatography coupled with tandem mass spectrometry. Method validation was performed on 22 pesticide residues in carrot, spinach and leek, at spiked levels of 5, 10 and 50 μg/kg, respectively. The average recoveries were between 70.1 and 119.5% with associated relative standard deviations

A multiresidue method for determining 12 carbamate pesticides in purple cabbage, orange, watermelon, cucumber, cowpea and Lactuca sativa L. employing multi-plug filtration cleanup (m-PFC) and ultra-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) was developed. M-PFC was carried out by cleanup at dispersive solid phase extraction (d-SPE), one m-PFC tip-filtration, two m-PFC tip-filtration and other methods (1–3 m-PFC cleanups). Results demonstrated that filtration simplified the cleanup method compared with d-SPE and other m-PFC methods (1–3 m-PFC cleanups). The method validation results showed that the method was linear, selective and accurate. The limits of quantification (LOQs) were 0.05–5.0 μg/kg, and the recoveries were in the range of 70.1–119.9% in different matrices. Although matrix effects were observed, they were successfully compensated using matrix-matched calibration. Finally, the developed method was successfully applied to detect pesticides in real samples.

A method employing a type of filtered solid phase extraction based on the PRiME hydrophilic lipophilic balance (HLB) was developed for extracting cephalosporin compounds (cephalexin monohydrate, cefradine, cefazolin, cefotaxime, cefmenoxime, cefoperazone sodium, cefadroxil, cefpirome sulfate, cefquinome sulfate, cefaclor, ceftizoxime, cephalonium, cephalothin sodium, cefamandole lithium, cefathiamidine, cefetamet pivoxyl) from milk samples. Compared to conventional HLB extraction, the PRiME HLB SPE process consists of only one step without activation, elution. It shows the advantage of a faster and better purifying capacity. Ultra-high pressure liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) was used for detection. In order to obtain high recoveries of the analytes, several parameters were optimized, such as variation of the extraction solvents, and the volume of the extraction solvent and dripping washing solution. With an optimized sample preparation, the limit of detection (LOD) and limit of quantification (LOQ) for the multi-reaction-monitoring (MRM) mode of the method varied from 0.02 to 5 μg kg−1, and 0.02 to 10 μg kg−1, respectively. Due to the different sensitivities of the analytes, the calibration curves were linear with R2 ≥ 0.991 in their linear ranges. The relative recoveries from the milk samples were between 56% and 93% with relative standard deviations lower than 15%.

An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/ MS) analytical method was established for the simultaneous determination of 24 forbidden industrial dyes in grain and meat products. The sample was extracted with methanol and acetonitrile, and cleaned-up by a WAX solid phase extraction column. The solution was separated on an ACQUITY UPLC BEH C18 column eluted with a mixture of 10 mmol/L ammonium acetate-0.2% formic acid aqueous solution and methanol-acetonitrile (7:3, v/v) as the mobile phases, and then analyzed in multiple reaction monitoring (MRM) mode. The correlation coefficients were above 0.99, the average recoveries were 61%-116%, and the relative standard deviations (RSD, n = 6) were lower than 13%. The quantification limits were 0.1-4.0 microg/kg. This method is simple, effective, sensitive, and suitable for the determination and confirmation of the 24 forbidden industrial dyes in grain and meat products.