title: Potentiometric flow injection sensing system for determination of heparin based on current-controlled release of protamine.
abstract: A flow injection system incorporated with a polycation-sensitive polymeric membrane electrode in the flow cell is proposed for potentiometric determination of heparin. An external current in nano-ampere scale is continuously applied across the polymeric membrane for controlled release of protamine from the inner filling solution to the sample solution, which makes the electrode membrane regenerate quickly after each measurement. The protamine released at membrane-sample interface is consumed by heparin injected into the flow cell via their strong electrostatic interaction, thus decreasing the measured potential, by which heparin can be detected. Under optimized conditions, a linear relationship between the potential peak height and the concentration of heparin in the sample solution can be obtained in the range of 0.1-2.0 U mL(-1), and the detection limit is 0.06 U mL(-1). The proposed potentiometric sensing system has been successfully applied to the determination of heparin in undiluted sheep whole blood.
authors.affiliation: Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Jiahong
authors.initials: J
authors.lastname: Lei
authors.affiliation: Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Jiawang
authors.initials: J
authors.lastname: Ding
authors.affiliation: Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Provincial Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China. Electronic address: wqin@yic.ac.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Qin
mesh_terms: D000818:Animals; D004566:Electrodes; D004867:Equipment Design; D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods*; D006493:Heparin / Q000097:blood* / Q000737:chemistry; D066298:In Vitro Techniques; D008567:Membranes, Artificial; D011073:Polyamines / Q000737:chemistry; D000071228:Polyelectrolytes; D011199:Potentiometry / Q000295:instrumentation / Q000379:methods*; D011479:Protamines / Q000032:analysis*; D012756:Sheep
chemical_list: D006493:Heparin; D008567:Membranes, Artificial; D011073:Polyamines; D000071228:Polyelectrolytes; D011479:Protamines
keywords: Current-controlled release; Flow injection analysis; Heparin; Polycation-sensitive membrane electrodes; Potentiometry; Protamine