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Geng C, Dong Z, Zhang T, Yang Z, Xu Z, Liang S, Ding X. Advances in atmospheric pressure plasma-based optical emission spectrometry for the analysis of heavy metals. Talanta 2024; 270:125634. [PMID: 38215585 DOI: 10.1016/j.talanta.2024.125634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 01/14/2024]
Abstract
Over the past decade, miniaturized optical emission spectrometry (OES) systems utilizing atmospheric pressure plasmas (APPs) as radiation sources have exhibited impressive capabilities in trace heavy metal analysis. As the core of the analytical system, APPs sources possess unique properties such as compact size, light weight, low energy requirement, ease of fabrication, and relatively low manufacturing cost. This critical review focuses on recent progress of APP-based OES systems employed for the determination of heavy metals. Influences of technical details including the sample introduction manner, the sampling volume, the sample flow rate, the pH of the solutions on the plasma stability and the intensity of analytical signals are comprehensively discussed. Furthermore, the review emphasizes the analytical challenges faced by these techniques and highlights the opportunities for further development in the field of heavy metal detection.
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Affiliation(s)
- Chaoqun Geng
- Department of Pharmaceutical Analysis, School of Pharmacy, Qingdao University, Qingdao, 266071, China
| | - Zheng Dong
- Shandong Qingdao Hospital of Integrated Traditional and Western Medicine, Qingdao, 266002, China
| | - Tiantian Zhang
- Department of Pharmaceutical Analysis, School of Pharmacy, Qingdao University, Qingdao, 266071, China
| | - Zhao Yang
- Qingdao Institute for Food and Drug Control, Qingdao 266071, China
| | - Zewen Xu
- Shandong Institute for Food and Drug Control, Jinan 250101, China
| | - Shuai Liang
- Department of Pharmaceutical Chemistry, School of Pharmacy, Qingdao University, Qingdao, 266071, China.
| | - Xuelu Ding
- Department of Pharmaceutical Analysis, School of Pharmacy, Qingdao University, Qingdao, 266071, China.
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2
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Angyus SB, Senila M, Frentiu T, Ponta M, Frentiu M, Covaci E. In-situ Diffusive Gradients in thin-films passive sampling coupled with ex-situ small-sized electrothermal vaporization capacitively coupled plasma microtorch optical emission spectrometry as green and white method for the simultaneous determination of labile species of toxic elements in surface water. Talanta 2023; 259:124551. [PMID: 37075518 DOI: 10.1016/j.talanta.2023.124551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/06/2023] [Accepted: 04/11/2023] [Indexed: 04/21/2023]
Abstract
This study presents for the first time the coupling between in-situ Diffusive Gradient in Thin-film (DGT) passive sampling technique and ex-situ small-sized instrumentation based on electrothermal vaporization capacitively coupled plasma microtorch optical emission spectrometry (SSETV-μCCP-OES) for the simultaneous determination of Cd, Pb, Cu, Zn and Hg in surface water. Unique features of the DGT-SSETV-μCCP-OES are low power and low Ar consumption for plasma generation (15 W, 150 mL min-1) and significant improvement of the detection limits following DGT passive sampling. The new method was validated in terms of river water analysis in comparison with graphite furnace atomic absorption spectrometry and thermal decomposition atomic absorption spectrometry. Combining the abilities of preconcentration by in-situ Chelex-DGT passive sampling with plasma microtorch equipped with a low resolution microspectrometer provided multielemental simultaneous determination with detection limits of (μg L-1) 0.01 (Cd, Zn and Hg), 0.02 (Cu) and 0.07 (Pb) in water, at least one order of magnitude better than using grab sampling without preconcentration. It was possible the quantification of labile fraction of priority hazardous metals (Cd, Pb) in river water below the instrumental limits of detection (μg L-1) of 0.12 and 0.80 obtained in SSETV-μCCP-OES without DGT sampling. The precision of the method was in the range 15.3-22.4% (combined uncertainty), while the accuracy was 95-103% and trueness of 27-33% (expanded uncertainty, k = 2). The DGT-SSETV-μCCP-OES coupling proved to be an ideal and powerful tool for surface water analysis in compliance with green and white analytical chemistry concepts. The application of the RGB-12 algorithm provided very good red/green (AGREEprep)/blue/white scores (%) of 100/80/98/93, determined primarily by in-situ DGT passive sampling, very good detection limits and cost-effective SSETV-μCCP-OES instrumentation.
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Affiliation(s)
- Simion Bogdan Angyus
- National Institute for Research and Development of Optoelectronics INOE 2000 INCD Bucharest, Research Institute for Analytical Instrumentation, Donath 67, 400293 Cluj-Napoca, Romania; Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, Arany Janos 11, 400028 Cluj-Napoca, Romania; Babes-Bolyai University, Research Center for Advanced Analysis, Instrumentation and Chemometrics, Arany Janos 11, 400028 Cluj-Napoca, Romania
| | - Marin Senila
- National Institute for Research and Development of Optoelectronics INOE 2000 INCD Bucharest, Research Institute for Analytical Instrumentation, Donath 67, 400293 Cluj-Napoca, Romania
| | - Tiberiu Frentiu
- Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, Arany Janos 11, 400028 Cluj-Napoca, Romania; Babes-Bolyai University, Research Center for Advanced Analysis, Instrumentation and Chemometrics, Arany Janos 11, 400028 Cluj-Napoca, Romania
| | - Michaela Ponta
- Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, Arany Janos 11, 400028 Cluj-Napoca, Romania; Babes-Bolyai University, Research Center for Advanced Analysis, Instrumentation and Chemometrics, Arany Janos 11, 400028 Cluj-Napoca, Romania
| | - Maria Frentiu
- National Institute for Research and Development of Optoelectronics INOE 2000 INCD Bucharest, Research Institute for Analytical Instrumentation, Donath 67, 400293 Cluj-Napoca, Romania
| | - Eniko Covaci
- Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, Arany Janos 11, 400028 Cluj-Napoca, Romania; Babes-Bolyai University, Research Center for Advanced Analysis, Instrumentation and Chemometrics, Arany Janos 11, 400028 Cluj-Napoca, Romania.
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3
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Zhong Y, Ji M, Hu Y, Li G, Xiao X. Progress of Environmental Sample Preparation for Elemental Analysis. J Chromatogr A 2022; 1681:463458. [DOI: 10.1016/j.chroma.2022.463458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 08/22/2022] [Accepted: 08/29/2022] [Indexed: 10/14/2022]
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4
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Direct coupling of liquid–liquid extraction with 3D-printed microplasma optical emission spectrometer for speciation analysis of mercury in fish oil. Microchem J 2022. [DOI: 10.1016/j.microc.2022.107569] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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5
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Cadar O, Mocan T, Roman C, Senila M. Analytical Performance and Validation of a Reliable Method Based on Graphite Furnace Atomic Absorption Spectrometry for the Determination of Gold Nanoparticles in Biological Tissues. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:3370. [PMID: 34947719 PMCID: PMC8708685 DOI: 10.3390/nano11123370] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/07/2021] [Accepted: 12/09/2021] [Indexed: 01/19/2023]
Abstract
Gold nanoparticles (AuNPs) have a wide-ranging application and are widespread in samples with complex matrices; thus, efficient analytical procedures are necessary to identify and characterize this analyte. A sensitive analytical method for determination of AuNPs content in biological tissues, based on microwave-assisted acid wet digestion and graphite furnace atomic absorption spectrometry (GFAAS) validated in accordance with the requirements of Eurachem guideline and ISO 17025 standard, is presented in this study. The digestion procedure was optimized, and the figures of merit such as selectivity, limit of detection (0.43 µg L-1), limit of quantification (1.29 µg L-1, corresponding to 12.9 µg kg-1 in tissue sample, considering the digestion), working range, linearity, repeatability ((RSDr 4.15%), intermediate precision (RSDR 8.07%), recovery in accuracy study (97%), were methodically evaluated. The measurement uncertainty was assessed considering the main sources of uncertainties and the calculated relative expanded uncertainty (k = 2) was 12.5%. The method was applied for the determination of AuNPs in six biological tissues (liver, small intestine, heart, lungs, brain and kidneys) and the found concentrations were generally at low levels, close or lower than LOQ.
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Affiliation(s)
- Oana Cadar
- INCDO-INOE 2000, Research Institute for Analytical Instrumentation, RO-400296 Cluj-Napoca, Romania; (O.C.); (C.R.)
| | - Teodora Mocan
- Physiology Department, “Iuliu Hatieganu” University of Medicine and Pharmacy, RO-400006 Cluj-Napoca, Romania;
- Nanomedicine Department, Regional Institute of Gastroenterology and Hepatology, RO-400158 Cluj-Napoca, Romania
| | - Cecilia Roman
- INCDO-INOE 2000, Research Institute for Analytical Instrumentation, RO-400296 Cluj-Napoca, Romania; (O.C.); (C.R.)
| | - Marin Senila
- INCDO-INOE 2000, Research Institute for Analytical Instrumentation, RO-400296 Cluj-Napoca, Romania; (O.C.); (C.R.)
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Silva NA, Nobre NF, Lopes GS. Rapid and Low Cost Determination of Total Mercury in Cat Foods by Photochemical Vapor Generation Coupled to Atomic Absorption Spectrometry. Biol Trace Elem Res 2021; 199:1161-1169. [PMID: 32472353 DOI: 10.1007/s12011-020-02216-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 05/20/2020] [Indexed: 10/24/2022]
Abstract
A rapid and low-cost method for determination of total mercury (THg) in cat food was developed based on photochemical vapor generation (PVG) coupled to cold vapor atomic absorption spectrometry (CVAAS). Cat food samples with ingredients based on tuna fish and other seafood were investigated. Organic acid precursor and concentration for radical generation and Hg photoreduction, sample UV irradiation time, and carrier gas flow were optimized. Highest PVG efficiency was achieved using 10% v v-1 formic acid, 4-s UV irradiation time, and a carrier gas flow of 50 mL min-1. The calibration function presented a correlation coefficient of 0.99. Accuracy was confirmed by analysis of Certified Reference Materials with recoveries of 93-110% and relative standard deviation lower than 6%. Under optimized conditions, a procedural detection limit of 0.28 μg kg-1 was obtained. Determination of THg in 10 samples of cat food purchased in local markets revealed a concentration range of 0.035-0.388 mg kg-1. Highest concentrations were found in cat foods. Only one sample presented a concentration close to the regulatory limit of the European Commission Directive. Assuming the estimated daily food intake (EDI) calculated in a range of 0.0021 to 0.023 mg of THg per day per kg body weight, it is concluded that it remains below that considered lethal for cats. The methodology is efficient, simple, low cost, and fit for purpose.
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Affiliation(s)
- Nilvan A Silva
- Laboratório de Estudos em Química Aplicada (LEQA), Departamento de Química Analítica e Físico-Química, Universidade Federal do Ceará, Campus do Pici, Fortaleza, CE, 60455-760, Brazil
| | - Nandressa F Nobre
- Laboratório de Estudos em Química Aplicada (LEQA), Departamento de Química Analítica e Físico-Química, Universidade Federal do Ceará, Campus do Pici, Fortaleza, CE, 60455-760, Brazil
| | - Gisele S Lopes
- Laboratório de Estudos em Química Aplicada (LEQA), Departamento de Química Analítica e Físico-Química, Universidade Federal do Ceará, Campus do Pici, Fortaleza, CE, 60455-760, Brazil.
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Mesa RL, Villa JEL, Khan S, Peixoto RRA, Morgano MA, Gonçalves LM, Sotomayor MDPT, Picasso G. Rational Design of an Ion-Imprinted Polymer for Aqueous Methylmercury Sorption. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E2541. [PMID: 33348754 PMCID: PMC7766906 DOI: 10.3390/nano10122541] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/16/2020] [Accepted: 11/23/2020] [Indexed: 02/06/2023]
Abstract
Methylmercury (MeHg+) is a mercury species that is very toxic for humans, and its monitoring and sorption from environmental samples of water are a public health concern. In this work, a combination of theory and experiment was used to rationally synthesize an ion-imprinted polymer (IIP) with the aim of the extraction of MeHg+ from samples of water. Interactions among MeHg+ and possible reaction components in the pre-polymerization stage were studied by computational simulation using density functional theory. Accordingly, 2-mercaptobenzimidazole (MBI) and 2-mercaptobenzothiazole (MBT), acrylic acid (AA) and ethanol were predicted as excellent sulfhydryl ligands, a functional monomer and porogenic solvent, respectively. Characterization studies by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) revealed the obtention of porous materials with specific surface areas of 11 m2 g-1 (IIP-MBI-AA) and 5.3 m2 g-1 (IIP-MBT-AA). Under optimized conditions, the maximum adsorption capacities were 157 µg g-1 (for IIP-MBI-AA) and 457 µg g-1 (for IIP-MBT-AA). The IIP-MBT-AA was selected for further experiments and application, and the selectivity coefficients were MeHg+/Hg2+ (0.86), MeHg+/Cd2+ (260), MeHg+/Pb2+ (288) and MeHg+/Zn2+ (1510), highlighting the material's high affinity for MeHg+. The IIP was successfully applied to the sorption of MeHg+ in river and tap water samples at environmentally relevant concentrations.
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Affiliation(s)
- Ruddy L. Mesa
- Laboratory of Physical Chemistry Research, Faculty of Sciences, National University of Engineering, Lima 15333, Peru; (R.L.M.M.); (S.K.)
| | - Javier E. L. Villa
- Institute of Chemistry, State University of São Paulo (UNESP), Araraquara, SP 14800-060, Brazil;
- National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT-DATREM), Araraquara, SP 14800-060, Brazil
| | - Sabir Khan
- Laboratory of Physical Chemistry Research, Faculty of Sciences, National University of Engineering, Lima 15333, Peru; (R.L.M.M.); (S.K.)
- Institute of Chemistry, State University of São Paulo (UNESP), Araraquara, SP 14800-060, Brazil;
- National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT-DATREM), Araraquara, SP 14800-060, Brazil
| | - Rafaella R. Alves Peixoto
- Department of Analytical Chemistry, Fluminense Federal University (UFF), Niterói, RJ 24020-150, Brazil;
| | | | | | - Maria D. P. T. Sotomayor
- Institute of Chemistry, State University of São Paulo (UNESP), Araraquara, SP 14800-060, Brazil;
- National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT-DATREM), Araraquara, SP 14800-060, Brazil
| | - Gino Picasso
- Laboratory of Physical Chemistry Research, Faculty of Sciences, National University of Engineering, Lima 15333, Peru; (R.L.M.M.); (S.K.)
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Borowska M, Jankowski K. Sensitive determination of bioaccessible mercury in complex matrix samples by combined photochemical vapor generation and solid phase microextraction coupled with microwave induced plasma optical emission spectrometry. Talanta 2020; 219:121162. [PMID: 32887092 DOI: 10.1016/j.talanta.2020.121162] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 05/15/2020] [Accepted: 05/18/2020] [Indexed: 12/21/2022]
Abstract
The photochemical generation technique of mercury vapor (PCVG) coupled with headspace solid phase microextraction (SPME) and microwave induced plasma optical emission spectrometry (MIP-OES) has been developed and successfully applied for fast and sensitive determination of mercury in complex matrix samples. Mercury vapor was generated by UV photo-reduction of inorganic mercury and methylmercury to mercury vapor in 5% (v/v) formic acid with subsequent gas-liquid separation and preconcentration by solid phase microextraction. A stopped-flow mode of the PCVG-SPME unit was employed with the aim of increasing analyte preconcentration factor, thus improving both sensitivity of determination and detection limits for mercury. The calibration curves were linear up to 20 ng mL-1 with the limit of detection for inorganic mercury and methylmercury of 0.030 and 0.045 ng mL-1, respectively. This manifold allowed a repeatability, expressed as relative standard deviation, of below 5%. Due to differences in efficiency of Hg vapor generation for Hg2+ and CH3Hg+, the quantification was performed against external Hg2+ and CH3Hg+ aqueous standards, respectively. The method was validated by the analysis of two CRM materials of different matrix composition, i.e. estuarine sediment ERM CC580 for total mercury content and tuna fish ERM CE464 for methylmercury content, respectively. The results proved good accuracy of the method with recovery of 101% total mercury and 87.3% methylmercury and precision of 3.8% and 12.5%, respectively. Effect of concomitants in the stopped-flow generation of mercury vapor with the new manifold was also investigated. Next, the proposed method was successfully applied for monitoring of bioaccessible fraction of mercury during their incubation in simulated body fluid in the presence of selenium nanoparticles examined as a potential mercury detoxifying agent.
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Affiliation(s)
- Magdalena Borowska
- Warsaw University of Technology, Faculty of Chemistry, Chair of Analytical Chemistry, Noakowskiego 3, 00-664, Warsaw, Poland.
| | - Krzysztof Jankowski
- Warsaw University of Technology, Faculty of Chemistry, Chair of Analytical Chemistry, Noakowskiego 3, 00-664, Warsaw, Poland
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Interference-free, green microanalytical method for total mercury and methylmercury determination in biological and environmental samples using small-sized electrothermal vaporization capacitively coupled plasma microtorch optical emission spectrometry. Talanta 2020; 217:121067. [PMID: 32498880 DOI: 10.1016/j.talanta.2020.121067] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/17/2020] [Accepted: 04/20/2020] [Indexed: 01/04/2023]
Abstract
An analytical method for the quantification of total Hg and CH3Hg+ in biological tissues (fish, mushroom) and water sediment was developed based on small-sized electrothermal vaporization capacitively coupled plasma microtorch optical emission spectrometry using a low-resolution microspectrometer as detector. Sample preparation was carried out according to the procedure recommended by JRC Technical Report of European Commission for the determination of CH3Hg+ in seafood and adapted by us for lower consumption of reagents. Amounts of 0.1 - 0.5 g sample were subjected to extraction in 5 ml of 47% HBr then CH3Hg+ was extracted in 2 × 1 ml toluene and back-extracted in 2 ml aqueous solution of 1% l-cysteine. Total Hg/CH3Hg+ were quantified in 10 μl of acidic extract/l-cysteine solution after electrothermal vaporization and measurement of 253.652 nm Hg signal in the episodic emission spectra. Under the optimal working conditions of system (70 °C sample drying, 1300 °C sample vaporization, 10 W plasma power and 150 ml min-1 Ar flow) the limits of detection were 7.0 μg kg-1 total Hg and 3.5 μg kg-1 CH3Hg+. Comparison of slopes in external calibration and standard addition procedure revealed the lack of non-spectral interferences of multimineral matrix, so that the calibration against Hg2+ standards was adopted. Pooled recovery of total mercury/methylmercury was 101 ± 7%/100 ± 7%, while precision assessed from measurements of real samples was in the range 1.6-9.6%/2.7-12.8%. The proposed method validated according to Eurachem Guide 2014 is selective and complies with demands in European legislation (Decisions 657/2002; 333/2007; 836/2011) and Association of Official Analytical Chemists Guide in terms of performances for food control. The method displays a high degree of greenness by circumventing cold vapor generation, use of small amounts of reagents and full-miniaturized instrumentation resulting in low analytical costs without reducing results quality. Besides, the method is simple and rapid, since it uses external calibration curves prepared from Hg2+standard solutions both for total Hg and CH3Hg+ determination.
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Shi MT, Yang XA, Qin LM, Zhang WB. Highly efficient electrocatalytic vapor generation of methylmercury based on the gold particles deposited glassy carbon electrode: A typical application for sensitive mercury speciation analysis in fish samples. Anal Chim Acta 2018; 1025:58-68. [DOI: 10.1016/j.aca.2018.04.057] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 04/20/2018] [Accepted: 04/21/2018] [Indexed: 11/26/2022]
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Covaci E, Angyus SB, Senila M, Ponta M, Darvasi E, Frentiu M, Frentiu T. Eco-scale non-chromatographic method for mercury speciation in fish using formic acid extraction and UV–Vis photochemical vapor generation capacitively coupled plasma microtorch optical emission spectrometry. Microchem J 2018. [DOI: 10.1016/j.microc.2018.05.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Cadar O, Pöllnitz A, Mărgineanu D, Silvestru C. Solid-state structure and solution behaviour of organomercury(II) compounds containing 2-(Me2NCH2)C6H4- moieties. Supramolecular aspects. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2017.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Covaci E, Senila M, Ponta M, Darvasi E, Frentiu M, Frentiu T. Mercury speciation in seafood using non-chromatographic chemical vapor generation capacitively coupled plasma microtorch optical emission spectrometry method – Evaluation of methylmercury exposure. Food Control 2017. [DOI: 10.1016/j.foodcont.2017.07.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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