Determination of mercury(II) in water samples using dispersive liquid-liquid microextraction and back extraction along with capillary zone electrophoresis
[Li, Jinhua; Lu, Wenhui; Chen, Lingxin] Chinese Acad Sci, Yantai Inst Coastal Zone Res, Shandong Prov Key Lab Coastal Zone Environm Proc, Key Lab Coastal Zone Environm Proc,CAS, Yantai 264003, Peoples R China; [Lu, Wenhui; Ma, Jiping] Qingdao Technol Univ, Inst Environm Municipal Engn, Key Lab Environm Engn Shandong Prov, Qingdao 266033, Peoples R China
通讯作者:
Chen, LX (reprint author), Chinese Acad Sci, Yantai Inst Coastal Zone Res, Shandong Prov Key Lab Coastal Zone Environm Proc, Key Lab Coastal Zone Environm Proc,CAS, Yantai 264003, Peoples R China
作者部门:
环境化学实验室
中文摘要:
We have developed a method for the determination of mercury in water samples that combines dispersive liquid-liquid microextraction (DLLME) with back-extraction (BE) and detection by capillary zone electrophoresis. DLLME is found to be a simple, cost-effective and rapid method for extraction and preconcentration. The BE procedure is based on the fact that the stability constant of the hydrophilic chelate of Hg(II) with L-cysteine is much larger than that of the respective complex with 1-(2-pyridylazo)-2-naphthol. Factors affecting complex formation and extraction efficiency (such as pH value, concentration of the chelating agent, time of ultrasonication and extraction, and type and quantity of disperser solvent) were optimized. Under the optimal conditions, the enrichment factor is 625, and the limit of detection is 0.62 mu g L(-1). The calibration plot is linear in the range between 1 and 1,000 mu g L(-1) (R (2) = 0.9991), and the relative standard deviation (RSD, for n = 6) is 4.1%. Recoveries were determined with tap water and seawater spiked at levels of 10 and 100 mu g L(-1), respectively, and ranged from 86.6% to 95.1%, with corresponding RSDs of 3.95-5.90%.
英文摘要:
We have developed a method for the determination of mercury in water samples that combines dispersive liquid-liquid microextraction (DLLME) with back-extraction (BE) and detection by capillary zone electrophoresis. DLLME is found to be a simple, cost-effective and rapid method for extraction and preconcentration. The BE procedure is based on the fact that the stability constant of the hydrophilic chelate of Hg(II) with L-cysteine is much larger than that of the respective complex with 1-(2-pyridylazo)-2-naphthol. Factors affecting complex formation and extraction efficiency (such as pH value, concentration of the chelating agent, time of ultrasonication and extraction, and type and quantity of disperser solvent) were optimized. Under the optimal conditions, the enrichment factor is 625, and the limit of detection is 0.62 mu g L(-1). The calibration plot is linear in the range between 1 and 1,000 mu g L(-1) (R (2) = 0.9991), and the relative standard deviation (RSD, for n = 6) is 4.1%. Recoveries were determined with tap water and seawater spiked at levels of 10 and 100 mu g L(-1), respectively, and ranged from 86.6% to 95.1%, with corresponding RSDs of 3.95-5.90%.
Determination of mercury(II) in water samples using dispersive liquid-liquid microextraction and back extraction along with capillary zone electrophoresis.pdf(229KB)
1.Chinese Acad Sci, Yantai Inst Coastal Zone Res, Shandong Prov Key Lab Coastal Zone Environm Proc, Key Lab Coastal Zone Environm Proc,CAS, Yantai 264003, Peoples R China 2.Qingdao Technol Univ, Inst Environm Municipal Engn, Key Lab Environm Engn Shandong Prov, Qingdao 266033, Peoples R China
Recommended Citation:
Li, Jinhua,Lu, Wenhui,Ma, Jiping,et al. Determination of mercury(II) in water samples using dispersive liquid-liquid microextraction and back extraction along with capillary zone electrophoresis[J]. MICROCHIMICA ACTA,2011,175(3-4):301-308.
Determination of mercury(II) in water samples using dispersive liquid-liquid microextraction and back extraction along with capillary zone electrophoresis.pdf