An electrochemical flow device has been developed for the determination of heavy metal ions(HMI)in water using multiwalled carbon nanotubes(MWCNTs)/Nafion(NA)/Hg electrode,by mean of diff erential pulse anodic strippi...An electrochemical flow device has been developed for the determination of heavy metal ions(HMI)in water using multiwalled carbon nanotubes(MWCNTs)/Nafion(NA)/Hg electrode,by mean of diff erential pulse anodic stripping voltammetry coupled with sequential injection analysis.The accuracy of the determination was ensured by the great electrical conductivity of MWCNTs and the high adsorption capacity of Hg.NA was used for MWCNTs immobilization for the long-term application of the electrode.The mercury film was cleaned after determination and another one would form during deposition.A lower limit of detection and a wider determination range of Cd^(2+)and Pb^(2+)could be achieved using the automatically analytical device combining with the MWCNTs/NA/Hg-modified electrode.The real-time monitoring of Cd^(2+)and Pb^(2+)in fresh water using this device continued for 10 days.The results indicated that the method was potential for on-site and real-time determination of HMI in water samples.展开更多
A novel differential pulse anodic stripping voltammetry for the determination of trace amounts of lead, using a biomacromolecule heparin drop-coated modified glassy carbon electrode, has been described. Pb2+ was depos...A novel differential pulse anodic stripping voltammetry for the determination of trace amounts of lead, using a biomacromolecule heparin drop-coated modified glassy carbon electrode, has been described. Pb2+ was deposited on the surface of a heparin-modified electrode at -1.0 V (vs. SCE) via forming Pb2+-heparin and subsequent re-duction at the electrode. In the following step, Pb-heparin was oxidized, and voltammograms were recorded by scanning the potential in a positive direction. Conditions were optimized with respect to the pH of the medium, the mass of drop-coated heparin, accumulation potential and accumulation time. The peak current was proportional to the Pb2+ concentration in the range of 2.0×10-9 to 7.0×10-7 mol/L. The detection limit was 3.0×10-10 mol/L. The relative standard deviation was 4.83% for 1.0×10-8 mol / L Pb2+ (n=10). The developed method has been applied to the determination of Pb2+ in water samples with satisfactory results.展开更多
目的:针对贝类中高毒重金属铅(Pb)和镉(Cd),开发一种可再生、廉价、快速、灵敏的电化学传感器。方法:以自制离子液体/石墨烯电极(IL/GNs HME)为工作电极,采用微分脉冲阳极溶出伏安法(DPASV)原位镀铋,根据得到的溶出峰电流,实现对Pb^(2+)...目的:针对贝类中高毒重金属铅(Pb)和镉(Cd),开发一种可再生、廉价、快速、灵敏的电化学传感器。方法:以自制离子液体/石墨烯电极(IL/GNs HME)为工作电极,采用微分脉冲阳极溶出伏安法(DPASV)原位镀铋,根据得到的溶出峰电流,实现对Pb^(2+)和Cd^(2+)的同步测定。结果:在铋离子质量浓度500μg/L,富集时间420 s,搅拌速度600 r/min,富集电压-1.1 V,缓冲体系HAc-Na Ac p H 4.2的条件下,利用电化学传感器测得的Pb^(2+)和Cd^(2+)的线性范围均为1.0~45.0μg/L,检测限分别达0.5μg/L和0.8μg/L。采用IL/GNs HME电化学传感器同时检测扇贝、褶牡蛎、长竹蛏、菲律宾蛤子中Pb^(2+)、Cd^(2+)含量时,所得结果均与电感耦合等离子体质谱(ICP-MS)检测结果相符。结论:基于IL/GNs HME构建的电化学传感器操作简便、灵敏度高,可实现对贝类中Pb^(2+)、Cd^(2+)含量的快速、同步测定。展开更多
基金financially supported by the marine high-tech industry development projects of Fujian Province(No.2015-19)
文摘An electrochemical flow device has been developed for the determination of heavy metal ions(HMI)in water using multiwalled carbon nanotubes(MWCNTs)/Nafion(NA)/Hg electrode,by mean of diff erential pulse anodic stripping voltammetry coupled with sequential injection analysis.The accuracy of the determination was ensured by the great electrical conductivity of MWCNTs and the high adsorption capacity of Hg.NA was used for MWCNTs immobilization for the long-term application of the electrode.The mercury film was cleaned after determination and another one would form during deposition.A lower limit of detection and a wider determination range of Cd^(2+)and Pb^(2+)could be achieved using the automatically analytical device combining with the MWCNTs/NA/Hg-modified electrode.The real-time monitoring of Cd^(2+)and Pb^(2+)in fresh water using this device continued for 10 days.The results indicated that the method was potential for on-site and real-time determination of HMI in water samples.
基金Project supported by the National Natural Science Foundation of China (No. 20377007).
文摘A novel differential pulse anodic stripping voltammetry for the determination of trace amounts of lead, using a biomacromolecule heparin drop-coated modified glassy carbon electrode, has been described. Pb2+ was deposited on the surface of a heparin-modified electrode at -1.0 V (vs. SCE) via forming Pb2+-heparin and subsequent re-duction at the electrode. In the following step, Pb-heparin was oxidized, and voltammograms were recorded by scanning the potential in a positive direction. Conditions were optimized with respect to the pH of the medium, the mass of drop-coated heparin, accumulation potential and accumulation time. The peak current was proportional to the Pb2+ concentration in the range of 2.0×10-9 to 7.0×10-7 mol/L. The detection limit was 3.0×10-10 mol/L. The relative standard deviation was 4.83% for 1.0×10-8 mol / L Pb2+ (n=10). The developed method has been applied to the determination of Pb2+ in water samples with satisfactory results.
文摘目的:针对贝类中高毒重金属铅(Pb)和镉(Cd),开发一种可再生、廉价、快速、灵敏的电化学传感器。方法:以自制离子液体/石墨烯电极(IL/GNs HME)为工作电极,采用微分脉冲阳极溶出伏安法(DPASV)原位镀铋,根据得到的溶出峰电流,实现对Pb^(2+)和Cd^(2+)的同步测定。结果:在铋离子质量浓度500μg/L,富集时间420 s,搅拌速度600 r/min,富集电压-1.1 V,缓冲体系HAc-Na Ac p H 4.2的条件下,利用电化学传感器测得的Pb^(2+)和Cd^(2+)的线性范围均为1.0~45.0μg/L,检测限分别达0.5μg/L和0.8μg/L。采用IL/GNs HME电化学传感器同时检测扇贝、褶牡蛎、长竹蛏、菲律宾蛤子中Pb^(2+)、Cd^(2+)含量时,所得结果均与电感耦合等离子体质谱(ICP-MS)检测结果相符。结论:基于IL/GNs HME构建的电化学传感器操作简便、灵敏度高,可实现对贝类中Pb^(2+)、Cd^(2+)含量的快速、同步测定。
