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Thoben C, Hartner NT, Hitzemann M, Raddatz CR, Eckermann M, Belder D, Zimmermann S. Regarding the Influence of Additives and Additional Plasma-Induced Chemical Ionization on Adduct Formation in ESI/IMS/MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:857-868. [PMID: 37052511 PMCID: PMC10161231 DOI: 10.1021/jasms.2c00348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Ion mobility spectrometers (IMS) separate ions based on their ion mobility, which depends mainly on collision cross-section, mass, and charge of the ions. However, the performance is often hampered in electrospray ionization (ESI) by the appearance of multiple ion mobility peaks in the spectrum for the same analyte due to clustering and additional sodium adducts. In this work, we investigate the influence of solvents and buffer additives on the detected ion mobility peaks using ESI. Additionally, we investigate the effects of an additional chemical ionization (CI) induced by plasma ionization on the ions formed by electrospray. For this purpose, we coupled our high-resolution IMS with a resolving power of Rp = 100 to a time-of-flight mass spectrometer. Depending on the analyte and the chosen additives, the ionization process can be influenced during the electrospray process. For the herbicide isoproturon, the addition of 5 mM sodium acetate results in the formation of the sodium adduct [M + Na]+, which is reflected in the ion mobility K0 of 1.22 cm2/(V·s). In contrast, the addition of 5 mM ammonium acetate yields the protonated species [M + H]+ and a correspondingly higher K0 of 1.29 cm2/(V·s). In some cases, as with the herbicide pyrimethanil, the addition of sodium acetate can completely suppress ionizations. By carefully choosing the solvent additive for ESI-IMS or additional CI, the formation of different ion mobility peaks can be observed. This can facilitate the assignment of ions to ion mobility peaks using IMS as a compact, stand-alone instrument, e.g., for on-site analysis.
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Affiliation(s)
- Christian Thoben
- Leibniz University Hannover, Institute of Electrical Engineering and Measurement Technology, Department of Sensors and Measurement Technology, Appelstr. 9A, 30167 Hannover, Germany
| | - Nora T Hartner
- Leipzig University, Institute of Analytical Chemistry, Linnéstraße 3, 04103 Leipzig, Germany
| | - Moritz Hitzemann
- Leibniz University Hannover, Institute of Electrical Engineering and Measurement Technology, Department of Sensors and Measurement Technology, Appelstr. 9A, 30167 Hannover, Germany
| | - Christian-Robert Raddatz
- Leibniz University Hannover, Institute of Electrical Engineering and Measurement Technology, Department of Sensors and Measurement Technology, Appelstr. 9A, 30167 Hannover, Germany
| | - Manuel Eckermann
- Leibniz University Hannover, Institute of Electrical Engineering and Measurement Technology, Department of Sensors and Measurement Technology, Appelstr. 9A, 30167 Hannover, Germany
| | - Detlev Belder
- Leipzig University, Institute of Analytical Chemistry, Linnéstraße 3, 04103 Leipzig, Germany
| | - Stefan Zimmermann
- Leibniz University Hannover, Institute of Electrical Engineering and Measurement Technology, Department of Sensors and Measurement Technology, Appelstr. 9A, 30167 Hannover, Germany
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Rahman MM, Lee DJ, Jo A, Yun SH, Eun JB, Im MH, Shim JH, Abd El-Aty AM. Onsite/on-field analysis of pesticide and veterinary drug residues by a state-of-art technology: A review. J Sep Sci 2021; 44:2310-2327. [PMID: 33773036 DOI: 10.1002/jssc.202001105] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 11/08/2022]
Abstract
Pesticides and veterinary drugs are generally employed to control pests and insects in crop and livestock farming. However, remaining residues are considered potentially hazardous to human health and the environment. Therefore, regular monitoring is required for assessing and legislation of pesticides and veterinary drugs. Various approaches to determining residues in various agricultural and animal food products have been reported. Most analytical methods involve sample extraction, purification (cleanup), and detection. Traditional sample preparation is time-consuming labor-intensive, expensive, and requires a large amount of toxic organic solvent, along with high probability for the decomposition of a compound before the analysis. Thus, modern sample preparation techniques, such as the quick, easy, cheap, effective, rugged, and safe method, have been widely accepted in the scientific community for its versatile application; however, it still requires a laboratory setup for the extraction and purification processes, which also involves the utilization of a toxic solvent. Therefore, it is crucial to elucidate recent technologies that are simple, portable, green, quick, and cost-effective for onsite and infield residue detections. Several technologies, such as surface-enhanced Raman spectroscopy, quantum dots, biosensing, and miniaturized gas chromatography, are now available. Further, several onsite techniques, such as ion mobility-mass spectrometry, are now being upgraded; some of them, although unable to analyze field sample directly, can analyze a large number of compounds within very short time (such as time-of-flight and Orbitrap mass spectrometry). Thus, to stay updated with scientific advances and analyze organic contaminants effectively and safely, it is necessary to study all of the state-of-art technology.
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Affiliation(s)
- Md Musfiqur Rahman
- Natural Products Chemistry Laboratory, Chonnam National University, Gwangju, Republic of Korea
| | - Dong Ju Lee
- Natural Products Chemistry Laboratory, Chonnam National University, Gwangju, Republic of Korea
| | - Ara Jo
- Natural Products Chemistry Laboratory, Chonnam National University, Gwangju, Republic of Korea
| | - Seung Hee Yun
- Natural Products Chemistry Laboratory, Chonnam National University, Gwangju, Republic of Korea
| | - Jong-Bang Eun
- Department of Food Science and Technology and BK 21 plus Program, Graduate School of Chonnam National University, Gwangju, Republic of Korea
| | - Moo-Hyeog Im
- Department of Food Engineering, Daegu University, Gyeongbuk, Republic of Korea
| | - Jae-Han Shim
- Natural Products Chemistry Laboratory, Chonnam National University, Gwangju, Republic of Korea
| | - A M Abd El-Aty
- Department of Pharmacology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt.,Department of Medical Pharmacology, Medical Faculty, Ataturk University, Erzurum, Turkey
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Alikord M, Mohammadi A, Kamankesh M, Shariatifar N. Food safety and quality assessment: comprehensive review and recent trends in the applications of ion mobility spectrometry (IMS). Crit Rev Food Sci Nutr 2021; 62:4833-4866. [PMID: 33554631 DOI: 10.1080/10408398.2021.1879003] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Ion mobility spectrometry (IMS) is an analytical separation and diagnostic technique that is simple and sensitive and a rapid response and low-priced technique for detecting trace levels of chemical compounds in different matrices. Chemical agents and environmental contaminants are successfully detected by IMS and have been recently considered to employ in food safety. In addition, IMS uses stand-alone or coupled analytical diagnostic tools with chromatographic and spectroscopic methods. Scientific publications show that IMS has been applied 21% in the pharmaceutical industry, 9% in environmental studies and 13% in quality control and food safety. Nevertheless, applications of IMS in food safety and quality analysis have not been adequately explored. This review presents the IMS-related analysis and focuses on the application of IMS in food safety and quality. This review presents the important topics including detection of traces of chemicals, rate of food spoilage and freshness, food adulteration and authenticity as well as natural toxins, pesticides, herbicides, fungicides, veterinary, and growth promoter drug residues. Further, persistent organic pollutants (POPs), acrylamide, polycyclic aromatic hydrocarbon (PAH), biogenic amines, nitrosamine, furfural, phenolic compounds, heavy metals, food packaging materials, melamine, and food additives were also examined for the first time. Therefore, it is logical to predict that the application of the IMS technique in food safety, food quality, and contaminant analysis will be impressively increased in the future. HighlightsCurrent status of IMS for residues and contaminant detection in food safety.To assess all the detected contaminants in food safety, for the first time.Identified IMS-related parameters and chemical compounds in food safety control.
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Affiliation(s)
- Mahsa Alikord
- Department of Environmental Health, Food Safety Division, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Abdorreza Mohammadi
- Department of Food Science and Technology, National Nutrition and Food Technology Research Institute, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Marzieh Kamankesh
- Cellular and Molecular Research Center, Sabzevar University of Medical Sciences, Sabzevar, Iran
| | - Nabi Shariatifar
- Department of Environmental Health, Food Safety Division, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.,Halal Research Center of the Islamic Republic of Iran, Tehran, Iran
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Current applications and perspectives of ion mobility spectrometry to answer chemical food safety issues. Trends Analyt Chem 2017. [DOI: 10.1016/j.trac.2017.07.006] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Aladaghlo Z, Fakhari AR, Hasheminasab KS. Application of electromembrane extraction followed by corona discharge ion mobility spectrometry analysis as a fast and sensitive technique for determination of tricyclic antidepressants in urine samples. Microchem J 2016. [DOI: 10.1016/j.microc.2016.05.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Kanu AB, Leal A. Identity Efficiency for High-Performance Ambient Pressure Ion Mobility Spectrometry. Anal Chem 2016; 88:3058-66. [DOI: 10.1021/acs.analchem.5b03765] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- A Bakarr Kanu
- Department of Chemistry, Winston-Salem State University, Winston-Salem, North Carolina 27110, United States
| | - Anne Leal
- Department of Chemistry, Winston-Salem State University, Winston-Salem, North Carolina 27110, United States
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High performance ion mobility spectrometry as a fast and low cost green analytical technology part I: analysis of nutritional supplements. ACTA ACUST UNITED AC 2011. [DOI: 10.1007/s12127-011-0072-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Dwivedi P, Schultz AJ, Hill HH. Metabolic Profiling of Human Blood by High Resolution Ion Mobility Mass Spectrometry (IM-MS). INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2010; 298:78-90. [PMID: 21113320 PMCID: PMC2990699 DOI: 10.1016/j.ijms.2010.02.007] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
A high resolution ion mobility time-of-flight mass spectrometer with electrospray ionization source (ESI-IM-MS) was evaluated as an analytical method for rapid analysis of complex biological samples such as human blood metabolome was investigated. The hybrid instrument (IM-MS) provided an average ion mobility resolving power of ~90 and a mass resolution of ~1500 (at m/z 100). A few µL of whole blood was extracted with methanol, centrifuged and infused into the IM-MS via an electrospray ionization source. Upon IM-MS profiling of the human blood metabolome approximately 1,100 metabolite ions were detected and 300 isomeric metabolites separated in short analyses time (30 minutes). Estimated concentration of the metabolites ranged from the low micromolar to the low nanomolar level. Various classes of metabolites (amino acids, organic acids, fatty acids, carbohydrates, purines and pyrimidines etc) were found to form characteristic mobility-mass correlation curves (MMCC) that aided in metabolite identification. Peaks corresponding to various sterol derivatives, estrogen derivatives, phosphocholines, prostaglandins, and cholesterol derivatives detected in the blood extract were found to occupy characteristic two dimensional IM-MS space. Low abundance metabolite peaks that can be lost in MS random noise were resolved from noise peaks by differentiation in mobility space. In addition, the peak capacity of MS increased six fold by coupling IMS prior to MS analysis.
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Affiliation(s)
- Prabha Dwivedi
- Washington State University, Pullman, WA, 99163 USA
- to whom correspondence should be addressed, () (Phone: 509-335-5648) (Fax: 509-335-8867), () (Phone: 509-335-7752) (Fax: 509-335-8867)
| | | | - Herbert H. Hill
- Washington State University, Pullman, WA, 99163 USA
- to whom correspondence should be addressed, () (Phone: 509-335-5648) (Fax: 509-335-8867), () (Phone: 509-335-7752) (Fax: 509-335-8867)
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Headley JV, Du JL, Peru KM, McMartin DW. Mass spectrometry of the photolysis of sulfonylurea herbicides in Prairie waters. MASS SPECTROMETRY REVIEWS 2010; 29:593-605. [PMID: 19890978 DOI: 10.1002/mas.20259] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This review of mass spectrometry of sulfonylurea herbicides includes a focus on studies relevant to Canadian Prairie waters. Emphasis is given to data gaps in the literature for the rates of photolysis of selected sulfonylurea herbicides in different water matrices. Specifically, results are evaluated for positive ion electrospray tandem mass spectrometry with liquid chromatography separation for the study of the photolysis of chlorsulfuron, tribenuron-methyl, thifensulfuron-methyl, metsulfuron-methyl, and ethametsulfuron-methyl. LC-MS/MS is shown to be the method of choice for the quantification of sulfonylurea herbicides with instrumental detection limits ranging from 1.3 to 7.2 pg (on-column). Tandem mass spectrometry coupled with the use of authentic standards likewise has proven to be well suited for the identification of transformation products. To date, however, the power of time-of-flight MS and ultrahigh resolution MS has not been exploited fully for the identification of unknown photolysis products. Dissipation of the herbicides under natural sunlight fit pseudo-first-order kinetics with half-life values ranging from 4.4 to 99 days. For simulated sunlight, radiation wavelengths shorter than 400 nm are required to induce significant photolytic reactions. The correlation between field dissipation studies and laboratory photolysis experiments suggests that photolysis is a major pathway for the dissipation of some sulfonylurea herbicides in natural Prairie waters.
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Affiliation(s)
- John V Headley
- Aquatic Ecosystem Research Protection Division, Water Science and Technology Directorate, Environment Canada, Saskatoon, Saskatchewan, Canada S7N 3H5.
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Krueger CA, Hilton CK, Osgood M, Wu J, Wu C. High resolution electrospray ionization ion mobility spectrometry. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s12127-009-0016-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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11
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Kanu AB, Gribb MM, Hill HH. Predicting optimal resolving power for ambient pressure ion mobility spectrometry. Anal Chem 2008; 80:6610-9. [PMID: 18683951 DOI: 10.1021/ac8008143] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although diffusion theory predicts that IMS resolving power increases with the square root of the voltage applied across the drift tube, in practice, there exists an optimum voltage above which resolving power decreases. This optimum voltage was determined to be both compound and initial ion pulse width dependent. A "conditional" resolving power equation is introduced that can be used to quickly approximate realistic resolving powers for specific instrumental operating parameters and compounds. Using four common environmental contaminants (trichloroethylene, tetrachloroethylene, methyl tert-butyl ether, methyl isobutyl ketone), diffusion-limited (theoretical), R d, conditional, R c, and actual (or measured), R m, IMS resolving powers were determined and compared for a small IMS instrument designed for subsurface measurements. Detection limits determined at the optimal resolving power for the environmental contaminants ranged from 18 parts per trillion volume-to-volume (ppt v) to 80 parts per billion volume-to-volume (ppb v). The maximal measured resolving power for our small, ambient-pressure stand-alone IMS ranged from 42 to 54, yielding an IMS resolving power efficiency, defined as R m/ R c x 100%, of 56-74% of the maximal conditional resolving power possible.
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Affiliation(s)
- Abu B Kanu
- Department of Chemistry, Prairie View A&M University, Prairie View, Texas 77446-0519, USA
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Steiner WE, English WA, Hill HH. Ion−Neutral Potential Models in Atmospheric Pressure Ion Mobility Time-of-Flight Mass Spectrometry IM(tof)MS. J Phys Chem A 2006; 110:1836-44. [PMID: 16451015 DOI: 10.1021/jp056158t] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The ion mobilities and their respective masses of several classes of amines (primary, secondary, and tertiary) were measured by electrospray ionization atmospheric pressure ion mobility time-of-flight mass spectrometry IM(tof)MS. The experimental data obtained were comparatively analyzed by the one-temperature kinetic theory of Chapman-Enskog. Several theoretical models were used to estimate the collision cross-sections; they include the rigid-sphere, polarization-limit, 12-6-4, and 12-4 potential models. These models were investigated to represent the interaction potentials contained within the collision integral that occurs between the polyatomic ions and the neutral drift gas molecules. The effectiveness of these collision cross-section models on predicting the mobility of these amine ions was explored. Moreover, the effects of drift gas selectivity on the reduced-mass term and in the collision cross-section term was examined. Use of a series of drift gases, namely, helium, neon, argon, nitrogen, and carbon dioxide, made it possible to distinguish between mass effects and polarizability effects. It was found that the modified 12-4 potential that compensates for the center of charge not being at the same location as the centers of mass showed improved agreement over the other collision cross-section models with respect to experimental data.
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Affiliation(s)
- Wes E Steiner
- SAIC/Geo-Centers, Edgewood Chemical Biological Center Operations, Aberdeen Proving Grounds, Maryland USA
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Baker SE, Olsson AO, Needham LL, Barr DB. High-performance liquid chromatography–tandem mass spectrometry method for quantifying sulfonylurea herbicides in human urine: reconsidering the validation process. Anal Bioanal Chem 2005; 383:963-76. [PMID: 16273339 DOI: 10.1007/s00216-005-0099-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2005] [Revised: 08/24/2005] [Accepted: 08/31/2005] [Indexed: 10/25/2022]
Abstract
We have developed a method for measuring 17 sulfonylurea (SU) herbicides in human urine. Urine samples were extracted using solid phase extraction (SPE), pre-concentrated, and analyzed by high-performance liquid chromatography-tandem mass spectrometry using turboionspray atmospheric pressure ionization. Carbon 13-labeled ethametsulfuron methyl was used as an internal standard. Chromatographic retention times were under 7 minutes. Total throughput was estimated as >100 samples per day. Because only one labeled internal standard was available for the analysis, we were forced to reconsider and restructure the validation process to include stringent stability tests and analyses of urine matrices of differing compositions. We describe our restructured validation process and the critical evaluation it provides for the method developed. The limits of detection (LOD) ranged from 0.05 microg/L to 0.10 microg/L with an average LOD of 0.06 microg/L. Average total relative standard deviations were 17%, 12% and 8% at 0.1 microg/L, 3.0 microg/L and 10 microg/L, respectively. Average extraction efficiencies of the SPE cartridges were 87% and 86% at 2.5 microg/L and 25 microg/L, respectively. Chemical degradation in acetonitrile and urine was monitored over 250 days. Estimated days for 10% and 50% degradation in urine and acetonitrile ranged from 0.7 days to >318 days. The influence of matrix effects on precision and accuracy was also explored.
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Affiliation(s)
- Samuel E Baker
- Centers for Disease Control and Prevention, Atlanta, GA 30341, USA
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Degelmann P, Wenger J, Niessner R, Knopp D. Development of a class-specific ELISA for sulfonylurea herbicides (sulfuron screen). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2004; 38:6795-6802. [PMID: 15669341 DOI: 10.1021/es0496266] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The development of a direct competitive ELISA for the detection of a broad range of sulfonylurea herbicides (SUs) is described. Polyclonal antibodies were generated in rabbits using three different immunizing haptens. Antiserum with the broadest specificity was obtained with a mesosulfuronbenzylamine derivative which was coupled via a succinic acid spacer to keyhole limpet hemocyanine. A heterologous enzyme tracer which did not contain the succinic acid bridge was prepared using activated horseradish peroxidase. The direct competitive ELISA was optimized and applied for spiked tap and surface water samples. From 30 SUs, 8 compounds showed a molar cross-reactivity (CR) higher than 100% (this value was set for the hapten) and 11 compounds CRs between 10% and 100%. The ELISA can detect 16 SUs at a concentration of 0.1 microg/L or lower. Different surface and tap water samples were spiked with chlorimuron ethyl, metsulfuron methyl, or primisulfuron methyl at concentrations of 100, 200, or 500 ng/L and subsequently analyzed by both ELISA and HPLC-UV. Correlation analysis revealed good agreement between both methods (r2 = 0.983/0.948/0.982; n = 21 for each analyte). Using ELISA, no sample pretreatment other than filtration was necessary.
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Affiliation(s)
- Petra Degelmann
- Institute of Hydrochemistry and Chemical Balneology, Technical University of Munich, Marchioninistrasse 17, D-81377 München, Germany
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Tam M, Hill HH. Secondary electrospray ionization-ion mobility spectrometry for explosive vapor detection. Anal Chem 2004; 76:2741-7. [PMID: 15144183 DOI: 10.1021/ac0354591] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The unique capability of secondary electrospray ionization (SESI) as a nonradioactive ionization source to detect analytes in both liquid and gaseous samples was evaluated using aqueous solutions of three common military explosives: cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX), nitroglycerin (NG) and pentaerythritol tetranitrate (PETN). The adducts formed between the compounds and their respective dissociation product, RDX.NO(2)(-), NG.NO(3)(-), and PETN.NO(3)(-), gave the most intense signal for the individual compound but were more sensitive to temperature than other species. These autoadducts were identified as RDX.NO(2)(-), NG.NO(3)(-), and PETN.NO(3)(-) and had maximum signal intensity at 137, 100, and 125 degrees C, respectively. The reduced mobility values of the three compounds were constant over the temperature range from 75 to 225 degrees C. The signal-to-noise ratios for RDX, NG, and PETN at 50 mg L(-1) in methanol-water were 340, 270, and 170, respectively, with a nominal noise of 8 +/- 2 pA. In addition to the investigation of autoadduct formation, the concept of doping the ionization source with nonvolatile adduct-forming agents was investigated and described for the first time. The SESI-IMS detection limit for RDX was 116 microg L(-1) in the presence of a traditional volatile chloride dopant and 5.30 microg L(-1) in the presence of a nonvolatile nitrate dopant. In addition to a lower detection limit, the nitrate dopant also produced a greater response sensitivity and a higher limit of linearity than did the traditional volatile chloride dopant.
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Affiliation(s)
- Maggie Tam
- Department of Chemistry, and Center for Multiphase Environmental Research, Washington State University, Pullman, Washington 99164, USA
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Current literature in mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2002; 37:765-776. [PMID: 12125010 DOI: 10.1002/jms.254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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