Quick, Easy, Cheap, Effective, Rugged, And Safe Procedure Research Articles

Simultaneous determination of sulfonylurea herbicides in tomatoes using the QuEChERS method coupled with HPLC

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 < 20% were achieved for all analytes at three spiked concentrations. The limits of detection and quantification for the 7 SUHs were 0.003 mg kg−1 and 0.008–0.009 mg kg−1, respectively. The developed method was subsequently used to quantify multi-residue SUHs during real sample analysis. None of the tested samples had SUH residue levels higher than the maximum residue limits established by the Korean Ministry of Food and Drug Safety. The results suggest that QuEChERS sample preparation employing a combination of C18 is a high-throughput and rapid clean-up procedure for the multi-residue analysis of SUHs in tomatoes.

Determination of teicoplanin and ramoplanin residues in aquaculture products by a modified QuEChERS method combined with UPLC-MS/MS

A QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method was developed to provide good analytical results for teicoplanin (TEC) and ramoplanin (RAM) residues in aquaticproducts. The analytes was extraction from aquatic product samples using chitosan in the QuEChERS procedure. Compared to conventional adsorbents, chitosan has a relatively good purification ability for the targets.The matrix effects of aquatic products, such as crucian carp, carp, silver carp, tilapia, mandarin fish, turbot, shrimp, sea cucumber and so on, were evaluated by high performance liquid chromatography coupled to triple-quadrupole tandem mass spectrometry. Throughout the validation experiments, the limits of detections and quantifications ranged from 0.4 ∼ 0.8 μg kg−1 and 1.0 ∼ 3.0 μg kg−1, respectively. Calibration curves showed correlation coefficient values higher than 0.998 in range between 1 and 100 μg kg−1. The recoveries ranged from 89.8 % to 110.0 % with relative standard deviation less than 7.2 % in nine typical aquaticproducts. The method shows low matrix effect (-18.5 %∼-2.6 %) for all targets in different aquaticproducts. The proposed methods proved to be reliable, effective and enables rapid determination of large batch samples, indicating its good applicability for detection and monitoring of TEC and RAM residues in aquaticproducts.

Limonun evde işlenmesi sırasında bazı insektisitlerin kalıntılarının değerlendirilmesi

The goal of this study was to assess the residues of some insecticides (abamectin, buprofezin, etoxazole) applied on the lemon fruits during its cultivation and to investigate the consequence of household processing such as peeling, jam production, freezing and storage on the residues. A multi-residual analysis method based on QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure and liquid chromatography coupled with triple quadrupole mass spectrometry was used. Mean recovery (measure of trueness; 70-120%), precision (as repeatability and interim precision relative standard deviation &amp;lt;20%) and limit of quantification (0.01 mg/kg &amp;lt; MRLs) were in accordance with the criteria set in the international guideline. Lemon samples were purchased from Bursa markets in April 2018. The experimental studies and statistical evaluations were conducted at Bursa University Agriculture Faculty (Bursa -Türkiye) between 5 May 2018-30 July 2022. The results revealed that pesticide residues mostly dispersed on the peel, therefore, peeling step decreased the residue level by 90-100% in the pulp of the fruit. Fruit juice and jam production operations decreased the residue level by 87- 100%. Processing factors were less than 1 for fruit juice and jam processing, on the other hand, it was greater than 1 for the separation, grating, freezing and storage of the peels.

Screening and quantification of pesticide residues in ciders by liquid chromatography-high resolution mass spectrometry

The present study aimed to apply a multi-residue method for the screening and quantification of pesticide residues in ciders, low alcoholic beverages made by fermentation of apple juice. Twenty bottled craft cider samples purchased from the Czech market were analysed for pesticide residues. The residues of pesticides were extracted from samples using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure in combination with additional solid-phase extraction (SPE) sample clean-up to achieve the lowest detection limit possible. In this study, targeted screening of pesticide residues in the samples was performed with the Q-Orbitrap mass spectrometry instrument. We identified 18 pesticides in cider samples analysed by screening method using an accurate-mass database of about 500 pesticide compounds, including their retention times, empirical formulas, and characteristic fragments. Additionally, liquid chromatography with high-resolution tandem mass spectrometer (LC-HRMS/MS) was used for re-analysis of positive findings of pesticides in samples and allowed to quantify compounds of interest at 0.2 µg L–1 concentration level. The monitoring scheme was applied to the set of craft ciders, and the results revealed the presence of pesticide residues in most of the samples at trace levels ranging from 0.5 to 5 µg L–1 and rarely at a level higher than 10 µg L–1.

Determination of the levels of tryptophan and 12 metabolites in milk by liquid chromatography-tandem mass spectrometry with the QuEChERS method

Tryptophan and metabolites have important biological functions in humans. Milk is an important source of tryptophan intake. In this study, we developed a method to detect levels of tryptophan and 12 metabolites in milk. The analytes were extracted by using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure and analyzed by liquid chromatography-tandem mass spectrometry with electrospray ionization. The proposed method resulted in suitable accuracy (standard deviation ≤10.31%) and high sensitivity (the limits of quantification were between 0.05 and 5 ng/mL). Recoveries were in the range of 44 to 126%. Finally, the developed method was successfully applied to compare the content of tryptophan and metabolites in 4 milk products produced by different processes: pasteurized milk, UHT milk, milk powder, and yogurt. The results of partial least squares-discriminant analysis (PLS-DA) showed that different types of processed milk could be distinguished clearly according to the method used here. The determined tryptophan and metabolites levels in milk can provide a new reference for evaluation of milk.

Determination of sulfonylurea pesticide residues in edible seeds used as nutraceuticals by QuEChERS in combination with ultra-high-performance liquid chromatography-tandem mass spectrometry

This work proposes a novel Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method in combination with ultra-high performance liquid chromatography-tandem mass spectrometry for the determination of sulfonylurea residues in edible seeds. The chromatographic separation of nine sulfonylureas was accomplished in less than 5.5 min, using a Luna Omega C18 column (50 × 2.1 mm, 1.6 µm). Mobile phase was supplied at 0.55 mL min-1 and consisted of 0.01% (v/v) aqueous acetic acid as eluent A and a mixture methanol/acetonitrile (80/20, v/v) as eluent B. Column temperature was established at 25 °C. A QuEChERS procedure was investigated as sample treatment for sulfonylureas extraction and sample clean-up. Different clean-up agents (i.e. PSA, Z-Sep+, EMR-Lipid and C18) were evaluated, selecting Z-Sep+ (25 mg) as the best option. The proposed method provided an extraction efficiency greater than 86.2%, while absolute matrix effect was lower than 50.1%. Matrix-matched calibration curves were required for analyte quantification. The analytical method was characterized according to SANTE/11813/2017 guideline, and including limits of detection and quantification, precision, and trueness. Linear dynamic ranges were established from 5 to 150 µg kg-1 for all analytes. Linearity (R2 ≥ 0.9974) and precision in terms of repeatability and intermediate precision (relative standard deviation ≤ 14.7%) are reported. The reporting limit was established at 5 µg kg−1, which is above the limits of quantification of the proposed method (≤ 1.64 µg kg−1) and below the maximum residue levels currently established by European legislation. In general, trueness is within the range of 70–120%. Despite greater recoveries were obtained at the reporting limit (i.e. 120–138%), relative standard deviations lower than 20% were obtained at this concentration level, so fulfilling the requirements of SANTE/11813/2017 guideline. This work represents the first analytical method intended for the analysis of sulfonylureas in sunflower, pumpkin and chia seeds, which are complex matrices due to their high content of fat as well as of growing interest due to their current commercialization as nutraceuticals.

Determination of 60 pesticides in hen eggs using the QuEChERS procedure followed by LC-MS/MS and GC-MS/MS

An analytical method involving QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation, followed by LC-MS/MS and GC-MS/MS was developed and validated for the determination of 60 pesticides in eggs. Recoveries of 70–120% were achieved for selected pesticides and relative standard deviations <20% were obtained for most analytes at three concentrations. The limit of quantification was <10 µg kg−1 for 83% of the total pesticides. This method was used to analyze 58 egg samples and the residues of seven pesticides (disulfoton, fipronil sulfone, cyromazine, o,p-DDT, p,p-DDD, p,p-DDT, and permethrin) were quantified in 16 egg samples at levels of 5–10 µg kg−1, which was below the corresponding the maximum residue levels, as established by Korean Ministry of Food and Drug Safety. We demonstrated that LC-MS/MS and GC-MS/MS in combination with QuEChERS can be used to routinely monitor multiple pesticide residues in egg samples.

Application of dispersive solid phase extraction for trace analysis of toxic chemicals in foods

The objectives of this study were to develop and validate a method for the identification of toxic organic chemicals, including groups of controlled substances, alkaloids and pesticides that are highly toxic and considered threats to public health. This project aims to ensure our laboratory's readiness to respond to emergencies involving our food supply in cooperation with the Food Emergency Response Network (FERN) program. The food matrices were homogenized in a blender or food processor prior to extraction with an acetonitrile-water mixture using a QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure. The extracts were then analyzed by either gas chromatography–mass spectrometry (GC–MS) or liquid chromatography-electrospray tandem mass spectrometry (LC-ESI/MS/MS). Method validation was performed on a variety of food matrices including lettuce, grapes, milk, chicken, pork and beef. MDLs for the toxic compounds ranged from 0.01 to 0.66 mg/kg (ppm). The findings in this study will provide a valuable resource for the determination of toxic chemicals in food matrices for emergency response situations.

Simultaneous determination of afidopyropen and its metabolite in vegetables, fruit and soil using UHPLC-MS/MS

ABSTRACTA new analytical method using the quick, easy, cheap, effective, rugged and safe (QuEChERS) procedure for simultaneous determination of afidopyropen and its metabolite M440I007 residues in tomato, watermelon, pepper, cucumber, pear, grape, cabbage and soil samples was developed using ultra-high performance liquid chromatography coupled with tandem mass spectrometry. The target compound was determined in less than 5.0 min using an electrospray ionisation source in positive mode (ESI+). The limit of quantification was 1 μg kg−1 in different matrices. Two sorbents primary secondary amine and graphitised carbon black were used in the QuEChERS procedure, and matrix-matched standards gave satisfactory recoveries and relative standard deviation (RSD) values in different matrices at three spiked levels (1, 10 and 500 μg kg−1). For afidopyropen, the recoveries ranged from 83% to 104% with an intra-day relative standard deviation (RSDr) of 1–8%, while they were from 80% to 103% with RSDr of 2–8% for M440I007. Reproducibility ranged between 1% and 19% for the three spiked levels.

Multiresidue Analysis of Five Neonicotinoid Insecticides and Their Primary Metabolite in Cucumbers and Soil Using High-Performance Liquid Chromatography with Diode-Array Detection.

A sensitive, selective, and validated HPLC-diode-array detection method was developed for the simultaneous determination of five neonicotinoid insecticides-acetamiprid, imidacloprid, nitenpyram, flonicamid, and thiacloprid-and their primary metabolite, 6-chloronicotinic acid, in cucumbers and soil based on the quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique as a pretreatment procedure. In the QuEChERS procedure, cucumber samples were extracted with acetonitrile and cleaned using C18, whereas soil samples were extracted with an acetonitrile-dichloromethane mixture (1 + 2). The HPLC conditions were optimized by separating neonicotinoids using an acetonitrile-water mixture (25 + 75) and a Synergi Hydro RP C18 column. Matrix-matched calibration standards were prepared in cucumber and soil to eliminate any matrix interference. RSDs were ≤9% in all recovery tests. LODs and LOQs for the five neonicotinoids were in the ranges of 0.006-0.122 and 0.018-0.366 μg/g, respectively. This method was successfully applied to determine residues, the rate of disappearance of the five neonicotinoids from cucumber and soil, and the half-lives of the neonicotinoids.

Revisiting quick, easy, cheap, effective, rugged, and safe parameters for sample preparation in pesticide residue analysis of lettuce by liquid chromatography–tandem mass spectrometry

A new analytical method using a quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure for multi-residue determination of 16 multiclass pesticides in five different types of lettuce was developed using high-performance liquid chromatography coupled to electrospray ionization tandem mass spectrometry. The QuEChERS procedure was optimized in terms of extractor solvent, partitioning salts and clean-up salts, through recovery, gravimetric analysis and matrix-effect studies. Microwave extraction and the use of disposable pipette extraction in the clean-up step were also tested, providing interesting alternatives to the traditional QuEChERS method, depending on the pesticides properties. The use of a laboratory-made phenyl-type sorbent, based on silica and poly(2-phenylpropyl)methylsiloxane, was studied in the clean-up step, presenting promising results as a substitute for primary secondary amine (PSA). The optimized QuEChERS method was defined employing acetonitrile, citrate buffer and clean-up with PSA, MgSO4 and graphitized carbon black. The method developed was validated according to Document SANTE/11945/2015 and proved to be selective, accurate and precise, obtaining limits of quantification from 5μgkg−1 and recoveries in the range of 70–120% with relative standard deviation≤20%. The method was applied on 14 real samples from commercial markets in Brazil and 21% of the samples analyzed presented irregularities, according to local pesticides regulations.

QuEChERS-based study on residue determination and dissipation of three herbicides in corn fields using HPLC-MS/MS

A rapid, simple, and selective analytical method was developed and validated for the simultaneous determination of florasulam, fluroxypyr, and fluroxypyr-meptyl in corn grain, plant, and soil using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure coupled with high-performance liquid chromatography-tandem mass spectrometry. The method gave mean recoveries in the range of 80%–108%, with limits of quantification ranging from 2 to 10 µg kg−1. The half-lives of the three compounds were 1.3–1.3, 0.7–1.3, and 0.7–1.3 days in plants, and 1.1–2.1, 0.4–1.3, and 0.4–1.3 days in soil. The terminal residues in all the matrices were found to be less than the limits of quantification at the pre-harvest intervals of 53 and 78 days. These results not only gave insights about the analytes but also contributed to the safe use of the broad-spectrum herbicides and a reference for establishing the maximum residue limit of florasulam in corn in China.

Simultaneous Determination of 27 Pesticides in Ginseng by UPLC/MS/MS and Modified QuEChERS Procedure

A novel, simple, and rapid method for the quantification of 27 commonly used pesticides in ginseng incorporating a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure was developed and validated. The pesticides were extracted with 1% acetic acid in acetonitrile and extracts purified by use of the mixed sorbents primary-secondary amine, C18, and graphitized carbon black. Quantitative analysis of all pesticides was performed by ultra-performance LC/MS/MS in the positive ionization mode in a single run due to the fast polarity switching capability of the mass spectrometer. Two precursor-product ion transitions were monitored for each compound in the multiple reaction monitoring mode. Quantification was carried out using matrix-matched standards for calibration. Recoveries of the proposed method from the spiked samples were achieved in the range 62.8-108.5%, and RSD ranged from 1.5 to 11.8%.

Multiresidue analysis of 213 pesticides in leek and garlic using QuEChERS-based method and gas chromatography-triple quadrupole mass spectrometry.

A simple and sensitive multiresidue pesticide analysis method was developed and validated for 213 pesticides in leek and garlic based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure combined with gas chromatography-triple quadrupole mass spectrometry. In the QuEChERS method, commercial extraction salt packet, dispersive solid-phase extraction adsorbent packet, and ceramic homogenizer were used to simplify the extraction procedure. The gas chromatography-tandem mass spectrometry (GC-MS/MS) parameters were optimized for analysis of 213 pesticides within a 38-min run time with a limit of quantification for most of the pesticides at 2 μg kg(-1). The coefficient of determination (r(2)) was >0.99 within the calibration linearity range of 2-400 μg kg(-1). Most recoveries at 2, 5, 10, 20, 50, 100, and 200 μg kg(-1) were in the range of 70-120% (n = 6) with associated relative standard deviations (RSDs) of <20%, indicating satisfactory precision. Real leek and garlic samples were analyzed for method application.

Assessment of two extraction methods to determine pesticides in soils, sediments and sludges. Application to the Túria River Basin

Pressurized liquid extraction (PLE) and Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction methods were optimized for the simultaneous determination of 50 pesticides in sediment, soils and sewage sludge. For QuEChERS development, several buffers and dispersive solid-phase extraction clean-up (dSPE) sorbents were tested. In the PLE method, several parameters affecting the extraction efficiency, such as organic solvent, amount of sample, cell size, temperature, pressure, static time, number of cycles and % of flush, as well as sorbent used for the on-line clean up, were also evaluated. PLE and QuEChERS were assessed and compared in obtained recoveries (33–89% versus 25–120%), number of pesticides for which recoveries are in the range of 80–100% (up to 13 versus up to 35) and cost of the approach. QuEChERS procedure was faster, cheaper and easier to perform. Recoveries were around 80% (at 50ngg−1 d.w.) and the matrix effect was less than −20% using matrix-matched standard calibration curve for most of the analytes. The limits of quantification were between 0.1 and 10ngg−1 (d.w.) except for alachlor and acetochlor. Repeatability and reproducibility were lower than 28% (%RSD, n=5). Soil, sediment and sludge samples, taken from the Túria River Basin, were analyzed by QuEChERS to determine pesticides. Chlorpyrifos (up to 65.3ngg−1 d.w.) was the most frequent and at higher concentrations. Thiabendazole, imazalil, diazinon, pyriproxyfen, hexythiazox, carbofuran, isoproturon, terbuthylazine and terbumeton were also found in some samples.

Multiresidue analysis of over 200 pesticides in cereals using a QuEChERS and gas chromatography–tandem mass spectrometry-based method

A simple and high-throughput multiresidue pesticide analysis method was developed and validated for 219 pesticides in cereals (corn, wheat flour and rice) based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure combined with gas chromatography–triple quadrupole mass spectrometry (GC–MS/MS). Different buffer system (acetate- and citrate-buffered) and sample to solvent ratios (sample amount) were compared in the modified QuEChERS procedure to get better recovery and clean-up results. The limits of quantification (LOQ) ranged between 5 and 50μgkg−1, and for the majority of the pesticides the LOQ were 5μgkg−1, which were below the regulatory maximum residue limits. The coefficient of determination (r2) was >0.99 within the calibration linearity range of 2–200μgkg−1 for the majority of the pesticides. Most recoveries at 5, 10, 20, 50, 100 and 200μgkg−1 were in the range 70–120% (n=6) with associated RSDs<20% indicating satisfactory accuracy.

Simultaneous determination of 11 quinolones in hotpot ingredients by dispersive solid-phase extraction and ultra performance liquid chromatography-tandem mass spectrometry

A method for the simultaneous determination of the residues of 11 quinolones in hotpot ingredients by quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction and ultra performance liquid chromatography-tandem mass spectrometric method (UPLC-MS/MS) was established. The sample was extracted with acetonitrile (containing 5% formic acid) and followed by stratifying with a salting-out agent. Clean-up of the extracts was processed by C18 and PSA, a modified QuEChERS procedure. The analytes were then separated on a Poroshell 120 EC-C18 column, and finally detected by tandem mass spectrometry in positive ESI mode. The linearity of all the 11 quinolones in the range from 1.0 to 100.0 microg/kg had correlation coefficients greater than 0.998. The limits of detection (LOD) of the method were from 1.8 to 3.1 microg/kg and the limits of quantification (LOQ) were from 6.0 to 10.3 microg/kg. The average recoveries of the 11 quinolones were in the range from 70.1% to 100.3%, with relative standard deviations from 2.42% to 10.88%. The established method is sensitive and of good recoveries. It can be applied as a rapid and reliable method for the determination of the 11 quinolones in hotpot ingredients.

Ultra-High Performance Liquid Chromatography/Electrospray Ionization-Tandem Mass Spectrometry Determination of 151 Pesticides in Soybeans and Pulses

This paper presents the application of ultra-high performance LC (UHPLC) and MS for the determination of 151 pesticides in soybeans and pulses. A core-shell particle (2.6 micro m particle size) column and a fully porous sub-2 microm (1.7 microm particle size) column showed comparable performance in chromatographic resolution and separation, increasing selectivity, and reducing analysis time. UHPLC was coupled with either a triple quadrupole mass analyzer (MS/MS) or a quadrupole Orbitrap (namely Orbital trap) mass spectrometer (Q-Orbitrap MS), which possesses fast data acquisition capability. Both configurations yielded analytical run times of < or =14 min. Soybean and pulse samples were analyzed and quantitated for pesticide residues using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure, UHPLC/electrospray ionization (ESI)-MS/MS, and matrix-matched standard calibration curves (in an analytical range of 5-500 microg/kg) with isotopically-labeled standards or a chemical analog as internal standards. The method performance parameters that included overall recovery, intermediate precision, and measurement uncertainty were evaluated according to a nested design experiment. Approximately 89% of the pesticides studied had recoveries between 81 and 110%; 95%, had intermediate precision < or =20%; and 93% showed measurement uncertainty < or =40%. From a pilot study of 100 samples, eight tested positive by UHPLCIESI-MS/MS for carbendazim, methomyl, or imidacloprid. These pesticides were further confirmed using UHPLC/ESI-Q-Orbitrap MS based on accurate mass measurement with mass error < or =5 ppm.

A novel multi-commutated method for the determination of hydroxytyrosol in enriched foods using mercaptopropionic acid-capped CdTe quantum dots

Hydroxytyrosol (HXT) has been reported to have beneficial effects for human health, such as antioxidant and antimicrobial properties and an important contribution to the prevention of cardiovascular disease. Hence, exhaustive research is currently being performed to prepare functional foods, such as tomato juice or milk, with HXT. This paper presents a multi-commutated flow method based on the quenching effect that HXT has on the fluorescence of water-soluble mercaptopropionic acid-capped CdTe quantum dots. Under optimal conditions a linear working range was obtained for concentrations between 10 and 250 ng µl−1. In order to demonstrate the suitability of the proposed method for the determination of HXT, HXT-enriched samples were prepared. Using a QuEChERS (quick, easy, cheap, effective, rugged and safe) procedure for extraction, HXT was determined in the prepared functional foods (milk, infant formula, tomato juice and tomato soup). Recoveries of 100% ± 8%, relative standard deviations (RSDs) lower than 5% and high sample throughput of 70 samples per h show the potential of the system for the analysis of HXT in food samples.

Simultaneous Determination of 44 Pesticides in Tobacco by UPLC/MS/MS and a Modified QuEChERS Procedure

A novel, simple, and rapid method for determination of the residues of 44 commonly used pesticides in tobacco was developed based on modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) procedures. The pesticides were extracted with acetonitrile and purified on a mixed sorbents column of primary secondary amine, C18, and graphitized carbon black. Quantitative determination of all pesticides was performed by ultra-performance LC/MS/MS in the positive or negative ionization mode by a single run due to the fast polarity switching capability of the mass spectrometer. Two precursor-product ion transitions were monitored for each compound in the multiple reaction monitoring mode. Quantification was carried out using matrix-matched standard calibration. The method has been validated by various tobacco cultivars, such as Burley, Oriental, and Virginia from different countries. Recoveries of the proposed method for spiked samples ranged from 71.1 to 109.8%, and RSD values were below 10%. The LOQ values were are all below the guidance residue levels proposed by the Agrochemical Advisory Committee of Cooperation Center for Scientific Research Relative to Tobacco. This method is valuable for measurement of pesticide residues in tobacco for QC and monitoring.