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Guibin Jiang - One of the best experts on this subject based on the ideXlab platform.
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evaluation of different extraction procedures for determination of organic mercury species in petroleum by high performance liquid chromatography coupled with cold vapor atomic fluorescence spectrometry
Talanta, 2013Co-Authors: Bin He, Zhenhua Wang, Thanh Wang, Guibin JiangAbstract:An extraction procedure for extracting organic mercury species including Methylmercury (MeHg) and ethylmercury (EtHg) from petroleum samples was developed. Three extraction methods (shaking, ultrasonic and microwave assisted extraction) using different extraction solvents (TMAH, KOH/CH3OH, HCI and acidic CuSO4/KBr) were investigated by comparing the extraction efficiency of the organic mercury species. Microwave assisted extraction at 60 W for 5 min using TMAH (tetramethylammonium hydroxide, 25%, m/v) provided the most satisfactory extraction efficiency for MeHg and EtHg in petroleum at 86.7% +/- 3.4% and 70.6% +/- 5.9%, respectively. Speciation analysis of mercury was done by on-line coupling of high performance liquid chromatography with cold vapor generation atomic fluorescence spectrometry (HPLC-CV-AFS). The proposed method was successfully applied to analyze several crude oil and light oil samples. The concentrations of MeHg ranged from under detection limit to 0.515 ng g(-1), whereas EtHg was not detected in the samples. This method can be a very useful tool in evaluating the risk of mercury emissions from petroleum. (C) 2012 Elsevier B.V. All rights reserved.
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dithizone functionalized solid phase extraction displacement elution high performance liquid chromatography inductively coupled plasma mass spectrometry for mercury speciation in water samples
Talanta, 2010Co-Authors: Yongguang Yin, Jingfu Liu, Jinfeng Peng, Ming Chen, Guibin JiangAbstract:A novel and simple solid phase extraction (SPE)-high performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry (ICP-MS) method was developed for determination of inorganic mercury (IHg), Methylmercury MeHg and ethylmercury (EtHg) in water samples in the present work The procedure involves pre-functionalization of the commercially available C18 SPE column with dithizone, loading water sample, displacement elution of mercury species by Na2S2O3 solution. followed by HPLC-ICP-MS determination Characterization and optimization of operation parameters of this new SPE procedure were discussed, including eluting reagent selection, concentration of eluting reagent, volume of eluting reagent, effect of NaCl and humic acid in sample matrix At optimized conditions, the detection limits of mercury species for 100 mL water sample were about 3 ng L-1 and the average recoveries were 93 7,83 4. and 71.7% for MeHg. IHg and EtHg, respectively, by spiking 0 2 mu g L-1 mercury species into de-ion water. Stability experiment reveals that both the dithizone-functionalized SPE cartridge and the mercury species incorporated were stable in the storage procedure These results obtained demonstrate that SPE-HPLC-ICP-MS is a simple and sensitive technique for the determination of mercury species at trace level in water samples with high reproducibility and accuracy (C) 2010 Elsevier B V All rights reserved.
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mercury speciation by a high performance liquid chromatography atomic fluorescence spectrometry hyphenated system with photo induced chemical vapour generation reagent in the mobile phase
Mikrochimica Acta, 2009Co-Authors: Yongguang Yin, Jingfu Liu, Jianbo Shi, Guibin JiangAbstract:Speciation of mercury was accomplished by using a simple interface with photo-induced chemical vapour generation in a high performance liquid chromatography—atomic fluorescence spectrometry (HPLC-AFS) hyphenated system. Acetic acid and 2-mercaptoethanol in the mobile phase were used as photochemical reagent. The operating parameters were optimized to give limits of detection of 0.53 µg L−1, 0.22 µg L−1, 0.18 µg L−1 and 0.25 µg L−1 for inorganic mercury, Methylmercury, ethylmercury and phenylmercury, respectively. The method was validated with the certified reference material DORM-2 and applied to the analysis of seafood samples. The HPLC-AFS hyphenated system is simple, environmentally friendly, and represents an attractive alternative to the conventional peroxothiosulfate-borohydride method.
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direct chemical vapour generation flame atomization as interface of high performance liquid chromatography atomic fluorescence spectrometry for speciation of mercury without using post column digestion
Journal of Analytical Atomic Spectrometry, 2009Co-Authors: Zhenhua Wang, Jinfeng Peng, Bin He, Guibin JiangAbstract:A high performance liquid chromatography-direct chemical vapour generation-flame atomization-atomic fluorescence spectrometry (HPLC-CVG-FA-AFS) system for speciation of Methylmercury (MeHg+), inorganic mercury (Hg2+) and ethylmercury (EtHg+) without using post-column digestion is developed and characterized. In this novel system, organomercurial species separated by chromatography were transformed to their hydrides by KBH4, further atomized in the flame atomizer and detected by AFS. The conventionally used on-line UV or microwave digestion system was omitted, and no oxidation reagent was needed, which significantly simplified the instrumentation. Under the optimized conditions, the detection limits were 0.2, 0.4 and 0.4 µg L−1 (as Hg) for MeHg+, Hg2+, and EtHg+ (100 µL injection), which corresponds to absolute detection limits of 0.02, 0.04 and 0.04 ng (as Hg) for MeHg+, Hg2+, and EtHg+, respectively. The sensitivity of the developed method was comparable with the conventional high performance liquid chromatography-UV digestion-cold vapour generation-atomic fluorescence spectrometry (HPLC-UV-CVG-AFS) system. Validation with biological certified reference materials showed that the proposed method is simple and accurate for mercury speciation.
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simple interface of high performance liquid chromatography atomic fluorescence spectrometry hyphenated system for speciation of mercury based on photo induced chemical vapour generation with formic acid in mobile phase as reaction reagent
Journal of Chromatography A, 2008Co-Authors: Bin He, Guibin JiangAbstract:Abstract Photo-induced chemical vapour generation (CVG) with formic acid in mobile phase as reaction reagent was developed as interface to on-line couple HPLC with atomic fluorescence spectrometry for the separation and determination of inorganic mercury, Methylmercury (MeHg), ethylmercury (EtHg) and phenylmercury (PhHg). In the developed procedure, formic acid in mobile phase was used to decompose organomercuries and reduce Hg2+ to mercury cold vapour under UV irradiation. Therefore, no post-column reagent was used and the flow injection system in traditional procedure is omitted. A number of operating parameters including pH of mobile phase, concentration of formate, flow rate of mobile phase, length of PTFE reaction coil, flow rate of carrier gas and Na2S2O3 in sample matrix were optimized. The limits of detection at the optimized conditions were 0.085, 0.033, 0.029 and 0.038 μg L−1 for inorganic mercury, MeHg, EtHg and PhHg, respectively. The developed method was validated by determination of certified reference material DORM-2 and was further applied in analyses of seafood samples from Yantai port, China. The UV-CVG with formic acid simplifies the instrumentation and reduces the analytical cost significantly.
Yan Jiang - One of the best experts on this subject based on the ideXlab platform.
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probing mercury species dna interactions by capillary electrophoresis with on line electrothermal atomic absorption spectrometric detection
Analytical Chemistry, 2006Co-Authors: Yan Li, Yan JiangAbstract:The interactions of inorganic mercury Hg(II), Methylmercury (MeHg(I)), ethylmercury (EtHg(I)), and phenylmercury (PhHg(I)) with DNA have been probed by capillary electrophoresis with on-line electrothermal atomic absorption spectrometric detection (CE-ETAAS) in combination with circular dichroism and Fourier transform infrared spectroscopy. The CE-ETAAS assay allows sensitive probing of the level of DNA damage by mercury species, extraction of thermodynamic and kinetic information on the interactions of mercury species with DNA, and provides direct evidence for the formation of mercury species−DNA adducts. The binding affinity of mercury species to DNA increases in order of Hg(II) < EtHg(I) ∼ PhHg(I) ∼ MeHg(I). The interactions of mercury species with DNA follow a first-order kinetics for mercury species and zero-order kinetics for DNA. Mercury highly covalently coordinates to endocyclic and exocyclic N sites of DNA bases. However, the interactions of DNA with mercuric species cause no transition of the D...
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development of an ambient temperature post column oxidation system for high performance liquid chromatography on line coupled with cold vapor atomic fluorescence spectrometry for mercury speciation in seafood
Journal of Analytical Atomic Spectrometry, 2005Co-Authors: Yan Li, Liming Dong, Yan Jiang, Shanwei Wang, Dongqing JiangAbstract:An efficient ambient temperature post-column oxidation system was developed for high-performance liquid chromatography online coupled with cold vapor atomic fluorescence spectrometry for mercury speciation analysis in seafood. The developed system does not require an external heat source, such as a hot water bath, microwave heating or UV irradiation, to decompose organomercury compounds into inorganic mercury ion (Hg(II)). Methylmercury (MeHg), ethylmercury (EtHg), phenylmercury (PhHg) and Hg(II) were baseline separated on an RP-C18 column with a mixture of methanol, acetonitrile and water (75 ∶ 5 ∶ 20) containing 0.01% m/v ammonium pyrrolidine dithiocarbamate (APDC) (pH 3.5) as the mobile phase. Online ambient temperature post-column oxidation of organomercury species eluted from the HPLC column was achieved by mixing the effluent with a 3% m/v K2S2O8 in 10% v/v HCl solution in a knotted reactor made of a 0.5 mm id × 200 cm long PTFE tube. The developed oxidation approach enhanced sensitivity for organomercury by a factor of 4 for MeHg, 3 for EtHg and 6 for PhHg, compared with that obtained without post-column oxidation. The detection limits for 100 μl injection were 0.19–0.27 μg l−1 (as Hg) in extract, corresponding to 4.75–6.75 μg kg−1 (as Hg) in fish tissue for a 50 ml final extract of 2 g tissue. The precision (RSD, n = 5) ranged from 1.8 to 2.8% for peak area, and from 1.7% to 2.9% for peak height at the 1 μg l−1 (as Hg) level. The method was validated by determination of Methylmercury in a certified reference material (DORM-2, dogfish muscle) and applied to the speciation analysis of mercury in local seafood samples.
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on line coupling of flow injection displacement sorption preconcentration to high performance liquid chromatography for speciation analysis of mercury in seafood
Journal of Chromatography A, 2004Co-Authors: Liming Dong, Xiuping Yan, Yan Jiang, Shanwei Wang, Dongqing JiangAbstract:A simple and cost-effective method for speciation analysis of trace mercury in seafood was developed by on-line coupling flow injection microcolumn displacement sorption preconcentration to high-performance liquid chromatography (HPLC) with UV detection. The methodology involved the presorption of the Cu-PDC (pyrrolidine dithiocarbamate) chelate onto a microcolumn packed with a cigarette filter sorbent, simultaneous preconcentration of Hg(II), Methylmercury (MeHg), ethylmercury (EtHg), and phenylmercury (PhHg) onto the microcolumn through a displacement reaction with the presorbed Cu-PDC, and their subsequent elution from the microcolumn for on-line HPLC separation. Interferences from heavy metal ions with lower stability of their PDC chelates relative to Cu-PDC were minimized without the need of any masking agents. With the consumption of 4.0 ml of sample solution, the enrichment factors were about 80. The detection limits were 10-25 ng g(-1) (as Hg) in fresh tissue. Precision (R.S.D. (%), n = 5) ranged from 2 to 3% at the 500 microg l(-1) (as Hg) level. The developed technique was validated by analyzing a certified reference material (DORM-2, dogfish-muscle), and was shown to be useful for mercury speciation in real seafood samples.
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selective measurement of ultratrace Methylmercury in fish by flow injection on line microcolumn displacement sorption preconcentration and separation coupled with electrothermal atomic absorption spectrometry
Analytical Chemistry, 2003Co-Authors: Xiuping Yan, Yan JiangAbstract:A novel nonchromatographic speciation technique for ultratrace Methylmercury in biological materials was developed by flow injection microcolumn displacement sorption preconcentration and separation coupled on-line with electrothermal atomic absorption spectrometry (ETAAS). In the developed technique, Cu(II) was first on-line complexed with diethyldithiocarbamate (DDTC), and the resultant Cu−DDTC was presorbed onto a microcolumn packed with the sorbent from a cigarette filter. Selective preconcentration of Methylmercury (MeHg) in the presence of Hg(II), ethylmercury (EtHg), and phenylmercury (PhHg) was achieved at pH 6.8 through loading the sample solution onto the microcolumn due to a displacement reaction between MeHg and the presorbed Cu−DDTC. The retained MeHg was subsequently eluted with 50 μL of ethanol and on-line determined by ETAAS. Interferences from coexisting heavy metal ions with lower stability of their DDTC complexes relative to Cu−DDTC were minimized without the need of any masking reagent...
Yongguang Yin - One of the best experts on this subject based on the ideXlab platform.
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dithizone functionalized solid phase extraction displacement elution high performance liquid chromatography inductively coupled plasma mass spectrometry for mercury speciation in water samples
Talanta, 2010Co-Authors: Yongguang Yin, Jingfu Liu, Jinfeng Peng, Ming Chen, Guibin JiangAbstract:A novel and simple solid phase extraction (SPE)-high performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry (ICP-MS) method was developed for determination of inorganic mercury (IHg), Methylmercury MeHg and ethylmercury (EtHg) in water samples in the present work The procedure involves pre-functionalization of the commercially available C18 SPE column with dithizone, loading water sample, displacement elution of mercury species by Na2S2O3 solution. followed by HPLC-ICP-MS determination Characterization and optimization of operation parameters of this new SPE procedure were discussed, including eluting reagent selection, concentration of eluting reagent, volume of eluting reagent, effect of NaCl and humic acid in sample matrix At optimized conditions, the detection limits of mercury species for 100 mL water sample were about 3 ng L-1 and the average recoveries were 93 7,83 4. and 71.7% for MeHg. IHg and EtHg, respectively, by spiking 0 2 mu g L-1 mercury species into de-ion water. Stability experiment reveals that both the dithizone-functionalized SPE cartridge and the mercury species incorporated were stable in the storage procedure These results obtained demonstrate that SPE-HPLC-ICP-MS is a simple and sensitive technique for the determination of mercury species at trace level in water samples with high reproducibility and accuracy (C) 2010 Elsevier B V All rights reserved.
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mercury speciation by a high performance liquid chromatography atomic fluorescence spectrometry hyphenated system with photo induced chemical vapour generation reagent in the mobile phase
Mikrochimica Acta, 2009Co-Authors: Yongguang Yin, Jingfu Liu, Jianbo Shi, Guibin JiangAbstract:Speciation of mercury was accomplished by using a simple interface with photo-induced chemical vapour generation in a high performance liquid chromatography—atomic fluorescence spectrometry (HPLC-AFS) hyphenated system. Acetic acid and 2-mercaptoethanol in the mobile phase were used as photochemical reagent. The operating parameters were optimized to give limits of detection of 0.53 µg L−1, 0.22 µg L−1, 0.18 µg L−1 and 0.25 µg L−1 for inorganic mercury, Methylmercury, ethylmercury and phenylmercury, respectively. The method was validated with the certified reference material DORM-2 and applied to the analysis of seafood samples. The HPLC-AFS hyphenated system is simple, environmentally friendly, and represents an attractive alternative to the conventional peroxothiosulfate-borohydride method.
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simple interface of high performance liquid chromatography atomic fluorescence spectrometry hyphenated system for speciation of mercury based on photo induced chemical vapour generation with formic acid in mobile phase as reaction reagent
Journal of Chromatography A, 2008Co-Authors: Yongguang Yin, Jingfu Liu, Jianbo Shi, Guibin JiangAbstract:Photo-induced chemical vapour generation (CVG) with formic acid in mobile phase as reaction reagent was developed as interface to online couple HPLC with atomic fluorescence spectrometry for the separation and determination of inorganic mercury, Methylmercury (MeHg), ethylmercury (EtHg) and phenylmercury (PhHg). In the developed procedure, formic acid in mobile phase was used to decompose organomercuries and reduce Hg2+ to mercury cold vapour under UV irradiation. Therefore, no post-column reagent was used and the flow injection system in traditional procedure is omitted. A number of operating parameters including pH of mobile phase, concentration of formate, flow rate of mobile phase, length of PTFE reaction coil, flow rate of carrier gas and Na2S2O3 in sample matrix were optimized. The limits of detection at the optimized conditions were 0.085, 0.033, 0.029 and 0.038 mu g L-1 for inorganic mercury, MeHg, EtHg and PhHg, respectively. The developed method was validated by determination of certified reference material DORM-2 and was further applied in analyses of seafood samples from Yantai port, China. The UV-CVG with formic acid simplifies the instrumentation and reduces the analytical cost significantly. (c) 2007 Elsevier B.V. All rights reserved.
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photo induced chemical vapour generation with formic acid novel interface for high performance liquid chromatography atomic fluorescence spectrometry hyphenated system and application in speciation of mercury
Journal of Analytical Atomic Spectrometry, 2007Co-Authors: Yongguang Yin, Jingfu Liu, Erle Gao, Guibin JiangAbstract:Based on a novel photo-induced chemical vapour generation (CVG) with formic acid instead of the conventional K2S2O8/KBH4 system, an on-line coupled HPLC and atomic fluorescence spectrometry procedure was developed for the speciation of inorganic mercury, Methylmercury (MeHg), ethylmercury (EtHg) and phenylmecury (PhHg). Under UV irradiation, the decomposition of organic mercury species and the reduction of Hg2+ could be completed in one step with this proposed photo-induced CVG system. The novel CVG system used formic acid only, which simplified the flow system and avoided the possibility of contamination originating from additional chemicals. A number of operating parameters including organic acid species, concentration of formic acid, pH, flow rate of formic acid and flow rate of carrier gas were optimized, and comparable method sensitivities with the conventional K2S2O8/KBH4 system were obtained. The limits of detection at the optimized conditions were 0.81, 0.20 and 0.87 μg L−1 for MeHg, EtHg and PhHg, respectively. The developed method was validated by determination of certified reference material DORM-2 and was further applied in determination of seafood samples. The new CVG system is simple, environmentally benign, and inexpensive for the speciation analysis of mercury. It is expected to have similar applications in other analytical atomic spectrometric techniques as well as speciation of other organic metal compounds.
Fernando Barbosa - One of the best experts on this subject based on the ideXlab platform.
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a simple method for Methylmercury inorganic mercury and ethylmercury determination in plasma samples by high performance liquid chromatography cold vapor inductively coupled plasma mass spectrometry
Analytica Chimica Acta, 2013Co-Authors: Samuel S De Souza, Andres D Campiglia, Fernando BarbosaAbstract:Abstract A simple and sensitive method with a fast sample preparation procedure is proposed for the determination of mercury species in plasma/serum. The method combines online high-performance liquid chromatography separation, Hg cold-vapor formation and inductively coupled plasma mass spectrometry detection. Prior to analysis, plasma (250 μL) was accurately pipetted into 15 mL conical tubes. Then, an extractant solution containing mercaptoethanol, L-cysteine and HCl was added to the samples following sonication for 10 min. Quantitative mercury extraction was achieved with the proposed procedure. Separation of mercury species was accomplished in less than 8 min on a C8 reverse phase column with a mobile phase containing 3% v/v methanol + 97% v/v (0.5% v/v 2-mercaptoethanol + 0.05% v/v formic acid). The method detection limits were found to be 12 ng L −1 , 5 ng L −1 and 4 ng L −1 for inorganic mercury, ethylmercury and Methylmercury, respectively. Method accuracy is traceable to Standard Reference Material (SRM) 966 Toxic Metals in Bovine Blood from NIST. Additional validation was provided by the analysis of a secondary reference serum sample from the INSQ-Canada. Finally, the method was successfully applied for the speciation of mercury in plasma samples collected from volunteers exposed to Methylmercury through fish consumption. For the first time to our knowledge, levels of different species of Hg in plasma samples from riverside populations exposed to MeHg were determined.
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mercury speciation in seafood samples by lc icp ms with a rapid ultrasound assisted extraction procedure application to the determination of mercury in brazilian seafood samples
Food Chemistry, 2011Co-Authors: Bruno Lemos Batista, Jairo Lisboa Rodrigues, Samuel S De Souza, Vanessa Cristina De Oliveira Souza, Fernando BarbosaAbstract:Abstract This paper describes a simple method for mercury speciation in seafood samples by LC–ICP-MS with a fast sample preparation procedure. Prior to analysis, mercury species were extracted from food samples with a solution containing mercaptoethanol, l -cysteine and HCl and sonication for 15 min. Separation of mercury species was accomplished in less than 5 min on a C8 reverse phase column with a mobile phase containing 0.05%-v/v mercaptoethanol, 0.4% m/v l -cysteine and 0.06 mol L −1 ammonium acetate. The method detection limits were found to be 0.25, 0.20 and 0.1 ng g −1 for inorganic mercury, ethylmercury and Methylmercury, respectively. Method accuracy is traceable to Certified Reference Materials (DOLT-3 and DORM-3) from the National Research Council Canada (NRCC). With the proposed method there is a considerable reduction of the time of sample preparation. Finally, the method was applied for the speciation of mercury in seafood samples purchased from the Brazilian market.
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Methylmercury and inorganic mercury determination in blood by using liquid chromatography with inductively coupled plasma mass spectrometry and a fast sample preparation procedure
Talanta, 2010Co-Authors: Jairo Lisboa Rodrigues, Samuel S De Souza, Vanessa Cristina De Oliveira Souza, Fernando BarbosaAbstract:Despite the necessity to differentiate chemical species of mercury in clinical specimens, there are a limited number of methods for this purpose. Then, this paper describes a simple method for the determination of Methylmercury and inorganic mercury in blood by using liquid chromatography with inductively coupled mass spectrometry (LC-ICP-MS) and a fast sample preparation procedure. Prior to analysis, blood (250microL) is accurately weighed into 15-mL conical tubes. Then, an extractant solution containing mercaptoethanol, l-cysteine and HCl was added to the samples following sonication for 15min. Quantitative mercury extraction was achieved with the proposed procedure. Separation of mercury species was accomplished in less than 5min on a C18 reverse-phase column with a mobile phase containing 0.05% (v/v) mercaptoethanol, 0.4% (m/v) l-cysteine, 0.06molL(-1) ammonium acetate and 5% (v/v) methanol. The method detection limits were found to be 0.25microgL(-1) and 0.1microgL(-1) for inorganic mercury and Methylmercury, respectively. Method accuracy is traceable to Standard Reference Material (SRM) 966 Toxic Metals in Bovine Blood from the National Institute of Standards and Technology (NIST). The proposed method was also applied to the speciation of mercury in blood samples collected from fish-eating communities and from rats exposed to thimerosal. With the proposed method there is a considerable reduction of the time of sample preparation prior to speciation of Hg by LC-ICP-MS. Finally, after the application of the proposed method, we demonstrated an interesting in vivo ethylmercury conversion to inorganic mercury.
Bin He - One of the best experts on this subject based on the ideXlab platform.
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evaluation of different extraction procedures for determination of organic mercury species in petroleum by high performance liquid chromatography coupled with cold vapor atomic fluorescence spectrometry
Talanta, 2013Co-Authors: Bin He, Zhenhua Wang, Thanh Wang, Guibin JiangAbstract:An extraction procedure for extracting organic mercury species including Methylmercury (MeHg) and ethylmercury (EtHg) from petroleum samples was developed. Three extraction methods (shaking, ultrasonic and microwave assisted extraction) using different extraction solvents (TMAH, KOH/CH3OH, HCI and acidic CuSO4/KBr) were investigated by comparing the extraction efficiency of the organic mercury species. Microwave assisted extraction at 60 W for 5 min using TMAH (tetramethylammonium hydroxide, 25%, m/v) provided the most satisfactory extraction efficiency for MeHg and EtHg in petroleum at 86.7% +/- 3.4% and 70.6% +/- 5.9%, respectively. Speciation analysis of mercury was done by on-line coupling of high performance liquid chromatography with cold vapor generation atomic fluorescence spectrometry (HPLC-CV-AFS). The proposed method was successfully applied to analyze several crude oil and light oil samples. The concentrations of MeHg ranged from under detection limit to 0.515 ng g(-1), whereas EtHg was not detected in the samples. This method can be a very useful tool in evaluating the risk of mercury emissions from petroleum. (C) 2012 Elsevier B.V. All rights reserved.
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direct chemical vapour generation flame atomization as interface of high performance liquid chromatography atomic fluorescence spectrometry for speciation of mercury without using post column digestion
Journal of Analytical Atomic Spectrometry, 2009Co-Authors: Zhenhua Wang, Jinfeng Peng, Bin He, Guibin JiangAbstract:A high performance liquid chromatography-direct chemical vapour generation-flame atomization-atomic fluorescence spectrometry (HPLC-CVG-FA-AFS) system for speciation of Methylmercury (MeHg+), inorganic mercury (Hg2+) and ethylmercury (EtHg+) without using post-column digestion is developed and characterized. In this novel system, organomercurial species separated by chromatography were transformed to their hydrides by KBH4, further atomized in the flame atomizer and detected by AFS. The conventionally used on-line UV or microwave digestion system was omitted, and no oxidation reagent was needed, which significantly simplified the instrumentation. Under the optimized conditions, the detection limits were 0.2, 0.4 and 0.4 µg L−1 (as Hg) for MeHg+, Hg2+, and EtHg+ (100 µL injection), which corresponds to absolute detection limits of 0.02, 0.04 and 0.04 ng (as Hg) for MeHg+, Hg2+, and EtHg+, respectively. The sensitivity of the developed method was comparable with the conventional high performance liquid chromatography-UV digestion-cold vapour generation-atomic fluorescence spectrometry (HPLC-UV-CVG-AFS) system. Validation with biological certified reference materials showed that the proposed method is simple and accurate for mercury speciation.
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simple interface of high performance liquid chromatography atomic fluorescence spectrometry hyphenated system for speciation of mercury based on photo induced chemical vapour generation with formic acid in mobile phase as reaction reagent
Journal of Chromatography A, 2008Co-Authors: Bin He, Guibin JiangAbstract:Abstract Photo-induced chemical vapour generation (CVG) with formic acid in mobile phase as reaction reagent was developed as interface to on-line couple HPLC with atomic fluorescence spectrometry for the separation and determination of inorganic mercury, Methylmercury (MeHg), ethylmercury (EtHg) and phenylmercury (PhHg). In the developed procedure, formic acid in mobile phase was used to decompose organomercuries and reduce Hg2+ to mercury cold vapour under UV irradiation. Therefore, no post-column reagent was used and the flow injection system in traditional procedure is omitted. A number of operating parameters including pH of mobile phase, concentration of formate, flow rate of mobile phase, length of PTFE reaction coil, flow rate of carrier gas and Na2S2O3 in sample matrix were optimized. The limits of detection at the optimized conditions were 0.085, 0.033, 0.029 and 0.038 μg L−1 for inorganic mercury, MeHg, EtHg and PhHg, respectively. The developed method was validated by determination of certified reference material DORM-2 and was further applied in analyses of seafood samples from Yantai port, China. The UV-CVG with formic acid simplifies the instrumentation and reduces the analytical cost significantly.