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A one-step QuEChERS automated detection technology for 22 pesticides in cowpeas and mangoes was established based on ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The sample was extracted by acetonitrile containing 1% acetic acid, added with EN extraction salt (anhydrous Mg2SO4, sodium chloride, trisodium citrate dihydrate, disodium hydrogen citrate sesquihydrate) to remove water, and then purified with C18 and graphitized carbon black (GCB). The target analytes were separated by ACQUITY UPLC BEH C18 chromatography column, using 0.01% formic acid aqueous solution (containing 2 mmol/L ammonium formate)-0.01% formic acid methanol as the mobile phase, and determined in multiple reaction monitoring (MRM). The results showed that the 22 pesticides had good linearity in the range of 0.01~25.00 µg/L, with coefficient of determination (R2) higher than 0.994. The limits of detection (LOD, S/N=3) were 0.05~2 µg/kg, and the limits of quantification (LOQ, S/N=10) were 0.1~5 µg/kg. At the spiked levels of 1×LOQ, 2×LOQ, and 10×LOQ, the average recoveries for cowpeas were 70.9%~116.6%, 71.9%~118.3%, and 73.7%~113.7%, respectively, and for mangoes were 70.2%~114.6%, 71.2%~113.7%, and 74.3%~118.5%, respectively. The relative standard deviations for them were all within 20%. The method was successfully applied to the detection of 42 actual samples, and 33 samples detected pesticide residues. This method has high sensitivity and a satisfactory level of automation, effectively reducing human operation steps. It is suitable for the simultaneous detection and accurate quantification of 22 pesticides and their metabolites.

This article established a rapid detection method for 34 pesticides in vegetables by combining QuEChERS purification method with high-performance liquid chromatography triple quadrupole linear ion trap tandem mass spectrometry. The samples were extracted with acetonitrile (containing 1% acetic acid), 1.5 g sodium acetate, 4 g anhydrous magnesium sulfate, and 1 g sodium chloride. The extract was further purified using 20 mg graphitized carbon black (GCB), 300 mg primary secondary amine (PSA), 200 mg octadecylsilane chemically bonded silica (C18), and 1000 mg MgSO4. Acetonitrile-water was chosen as mobile phase. The samples were analyzed using MRM-IDA-EPI mode, and an EPI database was established. Qualitative analysis was performed based on retention time, ion pair peak ratio, and EPI database, and quantification was carried out using matrix-matched external standard method. The study results indicated that using eggplant, garlic chives, cowpea, and spinach as representative matrices, the 34 pesticides showed good linear correlation with R2≥0.99011. The detection limits ranged from 0.16 to 1.81 μg/kg, and the quantification limits ranged from 0.52 to 6.02 μg/kg. The spiked recoveries of the samples were between 73.51% and 118.77%, and the precision was in the range of 0.01% to 14.27%. Vegetable samples were tested, with a detection rate of 58.23% for thiamethoxam. This method was characterized by its rapid and effective detection, simple operation, accurate data, and high sensitivity, making it suitable for the detection of 34 pesticides in vegetables.

An analysis method for simultaneous determination of 47 kinds of pesticide residues in tea was established by QuEChERS method combined with ultra performance liquid chromatography-tandem mass spectrometry. The samples were extracted by acetonitrile containing 1% acetic acid, and purified by QuEChERS method. The 47 pesticides were determined by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) with an electrospray ion source (ESI±) in positive and negative ion switching multiple reaction monitoring (MRM), and quantified by matrix-matched external standard method. Method validation revealed satisfactory linearities with correlation coefficients (r) between 0.9971 and 0.9996, and limits of detection were 0.001~0.006 mg/kg while the limits of quantitation were 0.002~0.020 mg/kg, the average recoveries at three spiked levels were in the range of 73.4%~114.3%, with relative standard deviations (n=6) of 0.3%~19.9%. The method is sensitive, accurate, stable, and can meet the requirements for determination of 47 pesticide residues in tea.

Abstract Background Plant hormones profoundly influence cotton growth, development, and responses to various stresses. Therefore, there is a pressing need for an efficient assay to quantify these hormones in cotton. In this groundbreaking study, we have established QuEChERS-HPLC‒MS/MS method, for the simultaneous detection of multiple plant hormones in cotton leaves, allowing the analysis and quantification of five key plant hormones. Results Sample extraction and purification employed 0.1% acetic acid in methanol and C18 for optimal recovery of plant hormones. The method applied to cotton demonstrated excellent linearity across a concentration range of 0.05–1 mg·L−1, with linear regression coefficients exceeding 0.99. The limits of quantification (LOQs) were 20 μg·kg−1 for GA3 and 5 μg·kg−1 for the other four plant hormones. Recovery rates for the five plant hormones matrix spiked at levels of 5, 10, 100, and 1000 μg·kg−1 were in the range of 79.07% to 98.97%, with intraday relative standard deviations (RSDs) ranging from 2.11% to 8.47%. The method was successfully employed to analyze and quantify the five analytes in cotton leaves treated with plant growth regulators. Conclusion The study demonstrates that the method is well-suited for the determination of five plant hormones in cotton. It exhibits excellent selectivity and sensitivity in detecting field samples, thus serving as a robust tool for in-depth research into cotton physiology.

Methicillin resistant Staphylococcus aureus harbouring other virulence factors in food is a serious threat to food safety. Delayed detection of MRSA may lead to fatal consequences due to the challenging treatment methods. To address the issue, early prognosis is prerequisite. We report one step QuEChERS detection method wherein, a media with selective agents such as cefoxitin, cyanidin, lithium chloride and methicillin (CCLM) was formulated for the specific cultivation and detection of MRSA within 5 hours. Direct application of the newly developed method was tested by screening food for MRSA and its comparison with conventional biochemical and molecular characterization. Growth of MRSA in the CCLM media was observed within 4 hours. This highly specific method is sensitive to detect 104 CFU/mL visually and 101 CFU/mL spectrophotometrically. 25% of food samples harboured MRSA which points to an immediate need of consideration by the authorities. The newly designed QuEChERS cyanin based chromogenic detection system is unequivocal with the conventional and molecular method of MRSA detection and can be of great use in diagnostic and in food safety laboratories.

Abstract The simultaneous determination of trace pesticides in complex matrices containing high concentrations of natural pigments remains challenging. In this study, quick, easy, cheap, effective, rugged, and safe (QuEChERS) sample preparation together with high-performance liquid chromatography with ultraviolet detection (HPLC–UV) was applied for the multi-residue analysis of seven sulfonylurea herbicides (SUHs) in tomatoes. SUH residue was extracted using the QuEChERS procedure, followed by solid-phase extraction (SPE) and dispersive SPE (d-SPE). To reduce the amount of carotenoids in tomato extracts, several d-SPE clean-up procedures were compared, and octadecylsilane (C18) provided the best color removal rate (%) of tomato extracts and recoveries (%) for all the tested SUHs. The validation results indicate good linearity (R2 > 0.9970), accuracy, and precision. Recoveries of 70–120% and relative standard deviations

Objective: An analysis method for simultaneous determination of 59 kinds of chemical drugs illegally added in herbal tea by micro-QuEChERS method combined with ultra performance liquid chromatography-tandem mass spectrometric (UPLC-MS/MS) was established. Method: The samples were extracted by ultrasonic extraction from acetonitrile solution for 5 min and salted out with sodium chloride (NaCl) and anhydrous sodium sulfate (Na2SO4). Supernatant was purified with C18 sorbent and separated on a ACQUITY HSS T3 column (100 mm×2.1mm, 1.8 μm) by gradient elution using a mixture of 0.01% formic acid and acetonitrile:methanol (8:2) as the mobile phase. Then the analytes were quantified by UHPLC-MS/MS in multiple reaction monitoring mode (MRM) via positive and negative electrospray ionization quantified by external standard method. Result: The coefficient of determination of the standard calibration curves for the 59 analytes were all above 0.9990. The limit of detection (LOD, S/N≥3) and the limit of quantitation (LOQ, S/N≥10) were 5.0~10.0 and 10.0~25 μg/L. At three spiked of 25.0, 50.0 and 100.0 μg/L, the average recoveries of 59 analytes were 60.3%~128.8% (n=6) with the relative standard deviations in the range of 1.0%～13.7%. Conclusion: The method developed was simple, sensitive, and had good purification effect. It could be applied for the rapid determination of 59 chemical drugs illegally added in herbal tea.

The aim of this study is to develop a modified QuEChERS method to analyze the thiamethoxam (TMX) and its metabolite clothianidin (CLO) in Okra. Using the developed analytical method the residue level of the neonicotinoid pesticides thiamethoxam (TMX) and its metabolite clothianidin (CLO) was determined in okra. The extraction was carried out using acetate buffer (1.5 g sodium acetate and 3.0 g anhydrous magnesium sulfate) in acetonitrile, and then the extract was cleaned up with optimized dispersive solid phase extraction (d-SPE) sorbents. The method linearity in a wide range (0.001–1.0 mg/L) with (R2≥0.9996), selectivity, accuracy (recoveries in the range of 86.9–97.8 %), precision (relative standard deviation (RSD) ≤ 5.8 %), limit of detection (LOD) and limit of quantification (LOQ) were 0.0007 and 0.002 mg/kg, respectively, and matrix suppression effect (ME) was observed -19.86 and -7.76 % for TMX and CLO, respectively. A total of 100 samples were collected from different market places in Dhaka, Bangladesh. The developed method coupled with LC-MS/MS was applied to determine the residue amount in the collected samples. In 43 % of the samples, TMX residues were found in the range of 0.0051- 0.214 mg/Kg. The maximum residue limit (MRL) of TMX and CLO in okra is 0.010 mg/kg; in 30 % of collected samples, TMX residue exceeds the MRL levels. The residue data were applied to estimate the human health risk.

This study was based on QuEChERS cleanup coupled with UHPLC-MS/MS for the determination of γ-oryzanol compounds in vegetable oils. Several parameters of QuEChERS and UHPLC-MS/MS were studied for purification and detection of γ-oryzanol compounds in oil samples. Under the optimized conditions, the whole pretreatment procedure could be accomplished within 10 min without tedious procedure, larger volume of organic solvent and complicated apparatus. The limit of detections and the limit of quantifications for γ-oryzanol compounds were ranging from 0.1-0.3 µg kg−1 and 0.4–1.0 µg kg−1, respectively. Satisfactory recoveries of all analyts were ranging from 72.2 % to 101.3 %, and the intra-day and inter-day precision were less than 10.6 %. The validation indicated that rice band oil and corn oil were rich in 24-mCAF, CAF, β-SIF, CMF and STF. The QuEChERS-UHPLC-MS/MS simultaneously quantified five γ-oryzanol compounds in lipid matrices and assessed the nutritional and functional substances of vegetable oils.

Emerging pollutants derived from human and animal sources, are present in soils and pose significant environmental and health impacts, even at low concentrations. Their detection in soil is analytically complex due to soil interference and the rapid degradation of compounds in the matrix. In this study, a protocol was optimized for quantifying hormonal steroids (n = 7), human drugs (n = 3), and antibiotics (n = 3) by a dual-phase extraction using QuEChERS and Solid Phase Extraction (SPE), followed by analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The double extraction phase allows an accurate and effective purification of the target compounds while eliminating the interference in the soil matrix. The method is optimized to detect environmental concentrations of these pollutants, to suit large-scale sampling campaigns and to maintain the efficiency of extraction while reducing analysis time. The limits of detection (LODs) of these compounds ranged between 0.0043 and 0.13 ng/g and recovery rates between 75.9 % and 105.39 %. • Enhanced Analyte Purification: Implements QuEChERS and SPE for robust removal of matrix interferences, optimizing target compound isolation. • Precision at Trace Levels: Secures LODs as minimal as 0.0043 ng/g, enabling accurate detection of low-concentration contaminants. • Adapted for Broad-scale sampling: Modifies extraction and analysis durations to accommodate large-scale environmental assessments.

In this study, an innovative method was developed to detect and quantify phthalates in fresh cetacean blubber. An adaptation of the ammonium formate QuEChERS method was used and adapted as a micro-extraction for small quantities of samples. Significantly, this technique utilized minimal quantities of reagents and salts, with the additional implementation of rigorous Quality Assurance/Quality Control protocols to further reduce background contamination. To ensure the reliability of this method, comprehensive validation procedures were conducted, with a specific focus on two widely studied cetacean species: the common bottlenose dolphin (Tursiops truncatus) and the short-finned pilot whale (Globicephala macrorhynchus). Determination coefficients (R2) for matrix-matched calibration were >0.93 with limits of quantifications (LOQ) of the method in the range of 5–10 ng/g. Mean recovery values were between 40 and 100 %. This novel methodology holds particular relevance for environmental research studies, offering the capability to detect emerging contaminants with minimal sample requirements. This aspect is particularly valuable in investigations that involve free-ranging animals and rely on biopsy sampling. It allows for the assessment of contaminant levels in healthy individuals within wild populations, enhancing our understanding of ecological impacts and potential conservation measures. • A micro-extraction adaptation of the ammonium formate QuEChERS method was developed and applied to a small quantity of fresh cetacean blubber to detect phthalates. • Small quantities of reagents and salts were used, and additional Quality Assurance/ Quality Control procedures were taken to further minimize background contamination. • Method validation was carried out for two cosmopolitan and extensively studied cetacean species: the common bottlenose dolphin (Tursiops truncatus) and the short-finned pilot whale (Globicephala macrorhynchus).

An analytical method based on quick, easy, cheap, effective, rugged and safe (QuEChERS) cleanup using an enhanced matrix removal lipid (EMR-Lipid) sorbent combined with ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was established for the rapid determination of 57 industrial dyes illegally added in foods. The sample was extracted with acetonitrile, and the extract was purified by QuEChERS. The analytes were separated on an Agilent ZORBAX Eclipse RRHD C18 column (3.0 mm × 150 mm, 1.8 μm) with gradient elution using a mobile phase composed of acetonitrile and 0.1% formic acid, detected using an electrospray ionization source operated under the positive mode with multiple reaction monitoring (MRM), and quantified by an external standard method. The results showed that good linearity was observed for all analytes in the concentration range from 20 to 300 ng/mL with correlation coefficients higher than 0.999. The limits of detection (LOD) and quantitation (LOQ) were 10 and 25 μg/kg, respectively. The recoveries at 3 spiked levels (25, 100 and 250 μg/kg) were 72.1%–119.1%, with relative standard deviations (RSDs, n = 6) of 0.19%–4.58%. The developed method was used to detect illegal addition of industrial dyes in soybean products, condiments, aquatic products, and meat products (n = 20 for each type). Alkaline yellow was detected in one bath of Sichuan pepper powder at a level of 32.9 μg/kg. In conclusion, this method is rapid, accurate, sensitive, and suitable for the determination of the 57 industrial dyes illegally added in foods.

The presence of veterinary drug residues in aquatic products represents a significant challenge to food safety. The current detection methods, limited in both scope and sensitivity, underscore the urgent need for more advanced techniques. This research introduces a swift and potent screening technique using high-performance liquid chromatography-high-resolution mass spectrometry (HPLC-HRMS) and a refined QuEChERS protocol, allowing simultaneous qualitative and semi-quantitative analysis of 192 residues. A comprehensive database, employing full scan mode and data-dependent secondary mass spectroscopy, enhances screening accuracy. The method involves efficient extraction using 90% acetonitrile, dehydration with Na2SO4, and acetic acid, followed by cleanup using dispersive solid-phase extract sorbent primary secondary amine. It is suitable for samples with varying fat content, offering detection limits ranging from 0.5 to 10 μg/kg, high recovery rates (60–120%), and low relative standard deviations (

A simple, rapid and novel method involving ultrahigh-performance liquid chromatography-electrospray ionization tandem triple quadrupole mass spectrometry (UHPLC-ESI–MS/MS) was developed to simultaneously detect erythromycin, its major metabolite and clarithromycin in chicken tissues (muscle, liver and kidney) and eggs (whole egg, albumen and yolk). Samples were extracted using acetonitrile–water (80:20, v/v), and a Cleanert MAS-Q cartridge was used to perform quick, easy, cheap, effective, rugged, and safe (QuEChERS) purification. The average recoveries were 87.78–104.22 %, and the corresponding intraday and interday relative standard deviations were less than 7.10 %. The decision limits and detection capabilities of the chicken tissues and eggs were 2.15–105.21 μg/kg and 2.26–110.42 μg/kg, respectively. For chicken tissues and eggs, the limits of detection and limits of quantification were 0.5 μg/kg and 2.0 μg/kg, respectively. The proposed method was successfully employed to analyse real samples, demonstrating its applicability.

Antibiotics and sedatives are used in freshwater fish culture and transportation, and residue in freshwater fish pose potential risks to human health. Therefore, a throughput method was developed to detect antibiotic and sedative residues in fish, simultaneously quantifying 68 antibiotics and 9 sedatives in freshwater fish using a modified QuEChERS extraction method and UPLC-MS/MS. Matrix-matched calibrations demonstrated good correlation coefficients (R2 > 0.995), with a recovery range of 66.2–118.5%. The intra-day and inter-day relative standard deviation (RSD) were below 9.7% and 12.8%, respectively. The limits of detection (LOD) and quantification (LOQ) were 0.08–1.46 μg/kg and 0.25–4.86 μg/kg, respectively. 68.8% of analytes had weak matrix effects, and 13.0% had moderate matrix effects. In addition, diazepam and many types of antibiotics were detected in30 freshwater fish. The validation parameters were in agreement with the acceptable criteria of the Codex guidelines. The method was effective in analyzing antibiotic and sedative residues in freshwater fish.

Polycyclic aromatic hydrocarbons (PAHs) are environmental contaminants that can be found in various food products, including those intended for infants. Due to their potential health risks, it is crucial to develop sensitive analytical methods for the accurate determination of PAHs in infant foods. This study describes the development and validation of a highly sensitive method for the quantification of European PAH markers, namely benzo[a]pyrene, benzo[a]anthracene, chrysene, and benzo[b]fluoranthene, using gas chromatography–tandem mass spectrometry (GC–MS/MS), in baby food samples. The first step was the optimization of the sample preparation procedure, performed using different methods based on the QuEChERS approach, also testing different extraction solvents. Several factors such as extraction efficiency, selectivity, and recovery were evaluated to choose the most effective procedure for sample preparation. Furthermore, the GC–MS/MS method was optimized, evaluating parameters such as linearity, sensitivity, accuracy, and robustness using spiked infant food samples. The method demonstrated excellent linearities with a correlation coefficient higher than 0.999 over a wide concentration range, and limits of detection and limits of quantification in the range 0.019–0.036 μg/kg and 0.06–0.11 μg/kg, respectively. Extraction recoveries were between 73.1 and 110.7%, with relative standard deviations always lower than 8%. These findings are compliant with the indications of the European Commission (Reg. 836/2011). To assess the applicability of the method to official control activities, a survey was conducted on commercially available infant food products. Four markers were determined in commercial samples belonging to different food categories for infants and young children. The outcome of this monitoring showed that PAH contamination, in all samples, was below the quantification limits. In conclusion, the developed GC–MS/MS method provides a highly sensitive and reliable approach for the determination of PAHs in baby foods. The optimized sample preparation, instrumental parameters, and validation results ensure accurate quantification of 4 PAHs even at trace levels. This method could contribute to the assessment of PAH exposure in infants and it could support regulatory efforts to ensure the safety and quality of infant food products with regular monitoring.