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1. Comparison of analyte identification criteria and other aspects in triple quadrupole tandem mass spectrometry: Case study using UHPLC-MS/MS for regulatory analysis of veterinary drug residues in liquid and powdered eggs

Author:
Steven J. Lehotay
Source:
Analytical and bioanalytical chemistry 2022 v.414 no.1 pp. 287-302
ISSN:
1618-2642
Subject:
USDA; case studies; chemical pollutants; chemical species; liquids; multiresidue analysis; mycotoxins; tandem mass spectrometry; ultra-performance liquid chromatography; veterinary drugs
Abstract:
... Ultrahigh-performance liquid chromatography (UHPLC) coupled with triple quadrupole tandem mass spectrometry (MS/MS) is one of the most powerful tools for the multiclass, multiresidue analysis of veterinary drugs, pesticides, mycotoxins, and other chemical contaminants in foods and other sample types. Until approximately 2010, commercial MS/MS instruments using multiple reaction monitoring (MRM) we ...
DOI:
10.1007/s00216-021-03380-x

2. Analysis of pesticides, veterinary drugs, and environmental contaminants in goat and lamb by the QuEChERSER mega-method

Author:
Steven J. Lehotay,   et al.   ; Ederina Ninga; Yelena Sapozhnikova; Alan R. Lightfield; Gary D. Strahan; Sergio H. Monteiro;     Show all 6 Authors
Source:
Analytical methods 2022 v.14 no.28 pp. 2761-2770
ISSN:
1759-9679
Subject:
automation; chemical species; data quality; gas chromatography; goats; labor; liquids; metabolites; muscles; pollution; polychlorinated biphenyls; sheep; tandem mass spectrometry; trade
Abstract:
... Analysis of chemical residues in foods is a big challenge for developing countries due to lack of financial and professional resources needed to meet international quality standards for trade. However, the implementation of simple multiclass, multi-residue methods in monitoring programs can provide significant benefits to save cost, time, and labor. The aim of this project was to investigate the “ ...
DOI:
10.1039/d2ay00713d

3. Validation of the QuEChERSER mega-method for the analysis of pesticides, veterinary drugs, and environmental contaminants in tilapia (Oreochromis Niloticus)

Author:
Steven J. Lehotay,   et al.   ; Sergio H. Monteiro; Yelena Sapozhnikova; Ederina Ninga; Graziela C.R. Moura Andrade; Alan R. Lightfield​;     Show all 6 Authors
Source:
Food additives & contaminants 2022 v.39 no.4 pp. 699-709
ISSN:
1944-0057
Subject:
Oreochromis niloticus; automation; chemical species; fish; food safety; freeze drying; gas chromatography; metabolites; muscles; pollution; polychlorinated biphenyls; robots; tandem mass spectrometry; ultra-performance liquid chromatography
Abstract:
... Diverse food safety programmes around the world are designed to help ensure production of safe food. To meet this need, the development and implementation of more efficient and effective analytical methods to monitor residues (pesticides and veterinary drugs) and contaminants in food is important. In this study, we report the validation results for a simple high-throughput mega-method for residual ...
Handle:
10113/7709667
DOI:
10.1080/19440049.2021.2020911

4. Validation of a high-throughput method for analysis of pesticide residues in hemp and hemp products

Author:
Steven J. Lehotay,   et al.   ; Nicolás Michlig; Alan R. Lightfield; Horacio Beldoménico; María Rosa Repetti;     Show all 5 Authors
Source:
Journal of chromatography 2021 v.1645 pp. 462097
ISSN:
0021-9673
Subject:
acetonitrile; automation; cannabinoids; centrifugation; chemical species; flowers; gas chromatography; hemp; metabolites; oils; pesticides; solvents; tandem mass spectrometry; ultra-performance liquid chromatography
Abstract:
... Hemp has been an agricultural commodity for millennia, and it has been undergoing a resurgence in interest and production due to its high content of cannabinoids, protein, fiber and other ingredients. For legal possession and use throughout the USA, hemp and hemp products must have delta-9-tetrahydrocannabinol (THC) concentration < 0.3%. As with most crops, pesticides may be applied when farming h ...
DOI:
10.1016/j.chroma.2021.462097

5. Comparison of four different multiclass, multiresidue sample preparation methods in the analysis of veterinary drugs in fish and other food matrices

Author:
Steven J. Lehotay,   et al.   ; Alan R. Lightfield;     Show all 2 Author
Source:
Analytical and bioanalytical chemistry 2021 v.413 no.12 pp. 3223-3241
ISSN:
1618-2642
Subject:
Food and Drug Administration; USDA; catfish; cattle; chemical species; food inspection; liquid chromatography; metabolites; muscles; reference standards; tandem mass spectrometry; veterinary drugs; China
Abstract:
... In 2018, AOAC International issued Standard Method Performance Requirements (SPMR) 2018.010 - Screening and Identification Method for Regulated Veterinary Drug Residues in Food. In response, we compared 4 different multiresidue methods of sample preparation using the same analytical method entailing ultrahigh-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). Tilapia was cho ...
DOI:
10.1007/s00216-021-03259-x

6. Less than one minute low-pressure gas chromatography - mass spectrometry

Author:
Steven J. Lehotay,   et al.   ; Alexander B. Fialkov; Aviv Amirav;     Show all 3 Authors
Source:
Journal of chromatography 2020 v.1612 pp. 460691
ISSN:
0021-9673
Subject:
biofuels; chemical species; cooling; fatty acid methyl esters; gas chromatography-mass spectrometry; helium; heroin; temperature
Abstract:
... Conventional gas chromatography - mass spectrometry (GC-MS) takes 20–40 min per sample, which is undesirably slow in any application if speed can be increased while still meeting analytical needs. In this study, we achieved reasonably good separations with full analysis cycle times of less than 1 min by combining for the first time low-pressure (LP) GC-MS with low thermal mass (LTM) resistive-heat ...
DOI:
10.1016/j.chroma.2019.460691

7. Assessment of Test Portion Sizes after Sample Comminution with Liquid Nitrogen in an Improved High-Throughput Method for Analysis of Pesticide Residues in Fruits and Vegetables

Author:
Steven J. Lehotay,   et al.   ; Nicolás Michlig; Alan R. Lightfield;     Show all 3 Authors
Source:
Journal of agricultural and food chemistry 2020 v.68 no.5 pp. 1468-1479
ISSN:
1520-5118
Subject:
apples; automation; broccoli; bulk commodities; cucumbers; data quality; freeze drying; fruits; gas chromatography; grapes; green beans; liquid chromatography; liquid nitrogen; magnesium sulfate; monitoring; peaches; pesticide residues; pesticides; portion size; quality control; reference standards; risk assessment; risk reduction; sodium chloride; squashes; standard deviation; tandem mass spectrometry; tomatoes; uncertainty
Abstract:
... In this study, sample processing of bulk commodities using an efficient one-step comminution procedure with liquid nitrogen (LN₂) was devised and assessed in the analysis of pesticide residues in fruits and vegetables. LN₂ was added to the fresh samples from a tank by opening a valve, and the standard food chopper was kept in a laboratory hood to reduce safety risks. Test portions of four replicat ...
DOI:
10.1021/acs.jafc.9b07685

8. Possibilities and Limitations of Isocratic Fast Liquid Chromatography-Tandem Mass Spectrometry Analysis of Pesticide Residues in Fruits and Vegetables

Author:
Steven J. Lehotay
Source:
Chromatographia 2019 v.82 no.1 pp. 235-250
ISSN:
0009-5893
Subject:
acetonitrile; ammonium; chemical species; cilantro; cucumbers; eggplants; foods; formates; fruits; liquid chromatography; methanol; monitoring; pH; pears; pesticide residues; pesticides; rapid methods; screening; tandem mass spectrometry; tomatoes
Abstract:
... Currently, state-of-the-art analytical methods for multiclass, multiresidue monitoring of pesticides in foods use ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) for analysis of LC-amenable analytes. UHPLC-MS/MS for > 100 pesticides typically takes 10 min per injection using gradient elution in the reversed-phase mode, plus typically 3–5 min for re-equilibration ...
DOI:
10.1007/s10337-018-3595-0

9. High-Throughput Mega-Method for the Analysis of Pesticides, Veterinary Drugs, and Environmental Contaminants by Ultra-High-Performance Liquid Chromatography–Tandem Mass Spectrometry and Robotic Mini-Solid-Phase Extraction Cleanup + Low-Pressure Gas Chromatography–Tandem Mass Spectrometry, Part 2: Catfish

Author:
Steven J. Lehotay,   et al.   ; Ederina Ninga; Yelena Sapozhnikova; Alan R. Lightfield; Sergio H. Monteiro;     Show all 5 Authors
Source:
Journal of agricultural and food chemistry 2020 v.69 no.4 pp. 1169-1174
ISSN:
1520-5118
Subject:
European Union; automation; catfish; chemical species; food chemistry; gas chromatography; liquid chromatography; metabolites; muscles; pollution; polychlorinated biphenyls; robots; tandem mass spectrometry
Abstract:
... The goal of this study was to develop and validate a new method for simultaneous determination of 106 veterinary drugs and 227 pesticides and their metabolites plus 16 polychlorinated biphenyls (PCBs) at and below their regulatory levels established for catfish muscle in the European Union and U.S.A. To do this, two different QuEChERS-based methods for veterinary drugs and pesticides and PCBs were ...
DOI:
10.1021/acs.jafc.0c00995

10. Critical review and re-assessment of analyte protectants in gas chromatography

Author:
Steven J. Lehotay,   et al.   ; Ruth Rodríguez-Ramos; Nicolás Michlig; Bárbara Socas-Rodríguez; Miguel Ángel Rodríguez-Delgado;     Show all 5 Authors
Source:
Journal of chromatography 2020 v.1632 pp. 461596
ISSN:
0021-9673
Subject:
calibration; chemical species; multiresidue analysis; pollution; shikimic acid; sorbitol
Abstract:
... Despite nearly 80 years of advancements in gas chromatography (GC), indirect chemical matrix effects (MEs), known as the matrix-induced response enhancement effect, still occur to cause a high bias in the GC analysis of susceptible analytes, unless precautions are taken. Matrix-matched calibration is one common option used in GC to compensate for the MEs, but this approach is usually inconvenient, ...
DOI:
10.1016/j.chroma.2020.461596

11. Hits and misses in research trends to monitor contaminants in foods

Author:
Steven J. Lehotay,   et al.   ; Yibai Chen;     Show all 2 Author
Source:
Analytical and bioanalytical chemistry 2018 v.410 no.22 pp. 5331-5351
ISSN:
1618-2642
Subject:
acrylamides; allergens; chemical pollutants; endocrine-disrupting chemicals; environmental protection; food additives; food industry; food safety; foods; furans; genetically modified organisms; growth promotion; melamine; metals; monitoring; nitrosamines; packaging; pesticides; pollution; risk assessment; scientists; toxicity; toxins; trade; veterinary drugs
Abstract:
... Monitoring of chemicals of toxicological concern in food is commonly needed for many purposes, which include (in part) food safety, regulatory enforcement, risk assessment, international food trade, label claims, environmental protection, industry needs, academic research, and consumer confidence. Chemicals of current concern include a variety of toxins, pesticides, veterinary drugs, growth promot ...
DOI:
10.1007/s00216-018-1195-3

12. Simultaneous analysis of aminoglycosides with many other classes of drug residues in bovine tissues by ultrahigh-performance liquid chromatography–tandem mass spectrometry using an ion-pairing reagent added to final extracts

Author:
Steven J. Lehotay,   et al.   ; Alan R. Lightfield;     Show all 2 Author
Source:
Analytical and bioanalytical chemistry 2018 v.410 no.3 pp. 1095-1109
ISSN:
1618-2642
Subject:
aminoglycoside antibiotics; aminoglycosides; capital; cattle; drug residues; food animals; kidneys; liquid chromatography; liver; monitoring; muscle tissues; tandem mass spectrometry; veterinary drugs
Abstract:
... The way to maximize scope of analysis, sample throughput, and laboratory efficiency in the monitoring of veterinary drug residues in food animals is to determine as many analytes as possible as fast as possible in as few methods as possible. Capital and overhead expenses are also reduced by using fewer instruments in the overall monitoring scheme. Traditionally, the highly polar aminoglycoside ant ...
DOI:
10.1007/s00216-017-0688-9

13. Cryogenic Sample Processing with Liquid Nitrogen for Effective and Efficient Monitoring of Pesticide Residues in Foods and Feeds

Author:
Steven J. Lehotay,   et al.   ; Manol Roussev; Julius Pollaehne;     Show all 3 Authors
Source:
Journal of agricultural and food chemistry 2019 v.67 no.33 pp. 9203-9209
ISSN:
1520-5118
Subject:
carbon disulfide; chemical species; cost effectiveness; dry ice; feeds; food processing; foods; liquid nitrogen; microextraction; mixing; monitoring; pesticide residues; portion size; thiram; viability
Abstract:
... With the monitoring of hundreds of pesticides in food and feed, the comminution step is equally crucial as any other to achieve valid results. However, sample processing is often underestimated in its importance and practical difficulty to produce consistent test portions for analysis. The scientific literature is rife with descriptions of microextraction methods, but ironically, sample comminutio ...
DOI:
10.1021/acs.jafc.9b04006

14. High-Throughput Mega-Method for the Analysis of Pesticides, Veterinary Drugs, and Environmental Contaminants by Ultra-High-Performance Liquid Chromatography−Tandem Mass Spectrometry and Robotic Mini-Solid-Phase Extraction Cleanup + Low-Pressure Gas Chromatography−Tandem Mass Spectrometry, Part 1: Beef

Author:
Steven J. Lehotay,   et al.   ; Sergio H. Monteiro; Yelena Sapozhnikova; Ederina Ninga; Alan R. Lightfield;     Show all 5 Authors
Source:
Journal of agricultural and food chemistry 2020 v.69 no.4 pp. 1159-1168
ISSN:
1520-5118
Subject:
automation; beef; cattle; chemical pollutants; chemical species; cost effectiveness; food chemistry; freeze drying; gas chromatography; international trade; labor; liquid chromatography; metabolites; muscles; pollution; polychlorinated biphenyls; reference standards; risk assessment; robots; solid phase extraction; standard deviation; tandem mass spectrometry
Abstract:
... In this work, a new mega-method of sample preparation called “QuEChERSER” (more than QuEChERS) is being presented for the first time. Fast, efficient, and cost-effective analysis of chemical contaminants in meat is useful for international trade, domestic monitoring, risk assessment, and other purposes. The goal of this study was to develop and validate a simple high-throughput mega-method for res ...
DOI:
10.1021/acs.jafc.0c00710

15. Use of a quality control approach to assess measurement uncertainty in the comparison of sample processing techniques in the analysis of pesticide residues in fruits and vegetables

Author:
Steven J. Lehotay,   et al.   ; Lijun Han; Yelena Sapozhnikova;     Show all 3 Authors
Source:
Analytical and bioanalytical chemistry 2018 v.410 no.22 pp. 5465-5479
ISSN:
1618-2642
Subject:
ambient temperature; apples; bananas; broccoli; celery; chopping; equipment; foods; freezing; fruits; gas chromatography; grapes; green beans; labor; monitoring; nitrogen; peaches; pesticide residues; portion size; potatoes; quality control; squashes; tandem mass spectrometry; ultra-performance liquid chromatography; uncertainty
Abstract:
... In routine monitoring of foods, reduction of analyzed test portion size generally leads to higher sample throughput, less labor, and lower costs of monitoring, but to meet analytical needs, the test portions still need to accurately represent the original bulk samples. With the intent to determine minimal fit-for-purpose sample size, analyses were conducted for up to 93 incurred and added pesticid ...
DOI:
10.1007/s00216-018-0905-1

16. Inter-laboratory validation of an inexpensive streamlined method to measure inorganic arsenic in rice grain

Author:
Steven J. Lehotay,   et al.   ; Rufus L. Chaney; Carrie E. Green;     Show all 3 Authors
Source:
Analytical and bioanalytical chemistry 2018 v.410 no.22 pp. 5703-5710
ISSN:
1618-2642
Subject:
acidity; arsenic; cacodylic acid; compliance; crop production; crops; high performance liquid chromatography; hydrides; hydrochloric acid; nitric acid; quality control; rice; spectroscopy; trade
Abstract:
... With the establishment by CODEX of a 200 ng/g limit of inorganic arsenic (iAs) in polished rice grain, more analyses of iAs will be necessary to ensure compliance in regulatory and trade applications, to assess quality control in commercial rice production, and to conduct research involving iAs in rice crops. Although analytical methods using high-performance liquid chromatography-inductively coup ...
DOI:
10.1007/s00216-018-1075-x

17. Use of an Efficient Measurement Uncertainty Approach To Compare Room Temperature and Cryogenic Sample Processing in the Analysis of Chemical Contaminants in Foods

Author:
Steven J. Lehotay,   et al.   ; Lijun Han; Yelena Sapozhnikova;     Show all 3 Authors
Source:
Journal of agricultural and food chemistry 2017 v.66 no.20 pp. 4986-4996
ISSN:
1520-5118
Subject:
ambient temperature; apples; automation; chemical pollutants; dry ice; gas chromatography; kale; liquids; nitrogen; portion size; quality control; salmon; solid phase extraction; tandem mass spectrometry; uncertainty
Abstract:
... In this study, analytical results were compared when using different approaches to bulk food sample comminution, consisting of a vertical chopper (Blixer) at room temperature and dry ice cryogenic conditions, followed by further subsample processing (20 g) using liquid nitrogen cryogenic conditions (cryomill). Analysis of the 43 targeted spiked and incurred contaminants in a food mixture consistin ...
DOI:
10.1021/acs.jafc.7b04359

18. Automated Mini-Column Solid-Phase Extraction Cleanup for High-Throughput Analysis of Chemical Contaminants in Foods by Low-Pressure Gas Chromatography—Tandem Mass Spectrometry

Author:
Steven J. Lehotay,   et al.   ; Lijun Han; Yelena Sapozhnikova;     Show all 3 Authors
Source:
Chromatographia 2016 v.79 no.17-18 pp. 1113-1130
ISSN:
0009-5893
Subject:
adsorbents; apples; avocados; basil; carrots; chemical analysis; computer software; food matrix; gas chromatography; humans; kale; labor; olives; pesticides; pollution; pork; salmon; solid phase extraction; tandem mass spectrometry; wheat
Abstract:
... This study demonstrated the application of an automated high-throughput mini-cartridge solid-phase extraction (mini-SPE) cleanup for the rapid low-pressure gas chromatography—tandem mass spectrometry (LPGC-MS/MS) analysis of pesticides and environmental contaminants in QuEChERS extracts of foods. Cleanup efficiencies and breakthrough volumes using different mini-SPE sorbents were compared using av ...
DOI:
10.1007/s10337-016-3116-y
PubMed:
27616781
PubMed Central:
PMC4995235

19. Method validation for 243 pesticides and environmental contaminants in meats and poultry by tandem mass spectrometry coupled to low-pressure gas chromatography and ultrahigh-performance liquid chromatography

Author:
Steven J. Lehotay,   et al.   ; Lijun Han; Yelena Sapozhnikova;     Show all 3 Authors
Source:
Food control 2016 v.66 pp. 270-282
ISSN:
0956-7135
Subject:
cattle; filtration; flame retardants; gas chromatography; muscles; pesticides; pollution; polybrominated diphenyl ethers; polychlorinated biphenyls; polycyclic aromatic hydrocarbons; poultry; poultry meat; solid phase extraction; swine; tandem mass spectrometry; ultra-performance liquid chromatography
Abstract:
... An easy and reliable high-throughput analysis method was developed and validated for 192 diverse pesticides and 51 environmental contaminants (13 PCB congeners, 14 PAHs, 7 PBDE congeners, and 17 novel flame retardants) in cattle, swine, and poultry muscle. Sample preparation was based on the “quick, easy, cheap, effective, rugged and safe” (QuEChERS) approach using filter-vial dispersive solid-pha ...
DOI:
10.1016/j.foodcont.2016.02.019

20. Evaluation of Different Parameters in the Extraction of Incurred Pesticides and Environmental Contaminants in Fish

Author:
Steven J. Lehotay,   et al.   ; Yelena Sapozhnikova;     Show all 2 Author
Source:
Journal of agricultural and food chemistry 2015 v.63 no.21 pp. 5163-5168
ISSN:
0021-8561
Subject:
acetonitrile; flame retardants; gas chromatography; mixing; pesticides; pollution; polybrominated diphenyl ethers; polychlorinated biphenyls; polycyclic aromatic hydrocarbons; salmon; solvents; tandem mass spectrometry; tissues; vibration; Lake Michigan
Abstract:
... Sample processing is often ignored during analytical method development and validation, but accurate results for real samples depend on all aspects of the analytical process. Also, validation is often conducted using only spiked samples, but extraction yields may be lower in incurred samples. In this study, different variables in extraction for incurred pesticides and environmental contaminants in ...
DOI:
10.1021/jf506256q