title: A pM leveled photoelectrochemical sensor for microcystin-LR based on surface molecularly imprinted TiO2@CNTs nanostructure.
abstract: A simple and highly sensitive photoelectrochemical (PEC) sensor towards Microcystin-LR (MC-LR), a kind of typical cyanobacterial toxin in water samples, was developed on a surface molecular imprinted TiO2coated multiwalled carbon nanotubes (MI-TiO2@CNTs) hybrid nanostructure. It was synthesized using a feasible two-step sol-gel method combining with in situ surface molecular imprinting technique (MIT). With a controllable core-shell tube casing structure, the resultant MI-TiO2@CNTs are enhanced greatly in visible-light driven response capacity. In comparison with the traditional TiO2(P25) and non-imprinted (NI-)TiO2@CNTs, the MI-TiO2@CNTs based PEC sensor showed a much higher photoelectric oxidation capacity towards MC-LR. Using this sensor, the determination of MC-LR was doable in a wide linear range from 1.0pM to 3.0nM with a high photocurrent response sensitivity. An outstanding selectivity towards MC-LR was further achieved with this sensor, proven by simultaneously monitoring 100-fold potential co-existing interferences. The superiority of the obtained MC-LR sensor in sensitivity and selectivity is mainly attributed to the high specific surface area and excellent photoelectric activity of TiO2@CNTs heterojunction structure, as well as the abundant active recognition sites on its functionalized molecular imprinting surface. A promising PEC analysis platform with high sensitivity and selectivity for MC-LR has thus been provided.
authors.affiliation: School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Siping Road 1239, Shanghai 200092, China.
authors.forename: Meichuan
authors.initials: M
authors.lastname: Liu
authors.affiliation: School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Siping Road 1239, Shanghai 200092, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Ding
authors.affiliation: School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Siping Road 1239, Shanghai 200092, China.
authors.forename: Qiwei
authors.initials: Q
authors.lastname: Yang
authors.affiliation: School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Siping Road 1239, Shanghai 200092, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Siping Road 1239, Shanghai 200092, China. Electronic address: g.zhao@tongji.edu.cn.
authors.forename: Guohua
authors.initials: G
authors.lastname: Zhao
authors.affiliation: Institute of Materials Engineering, University of Siegen, Paul-Bonatz Str. 9-11, Siegen 57076, Germany. Electronic address: nianjun.yang@uni-siegen.de.
authors.forename: Nianjun
authors.initials: N
authors.lastname: Yang
mesh_terms: D055664:Electrochemical Techniques; D008387:Marine Toxins; D052998:Microcystins / Q000032:analysis*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D055668:Photochemical Processes; D014025:Titanium / Q000737:chemistry*
chemical_list: D008387:Marine Toxins; D052998:Microcystins; D037742:Nanotubes, Carbon; C009495:titanium dioxide; D014025:Titanium; C057862:cyanoginosin LR
keywords: MI-TiO(2)@CNTs; Microcystin-LR; Molecular imprinting technique; Photoelectrochemical sensor