title: Fabrication of DNA functionalized carbon nanotubes/Cu(2+) complex by one-step electrodeposition and its sensitive determination of nitrite.
abstract: In this paper, DNA functionalized single-wall carbon nanotubes/Cu(2+) (DNA-CNTs/Cu(2+)) complex was one-step electrodeposited onto the glassy carbon electrode (GCE), which fabricated a DNA-CNTs/Cu(2+)/GCE sensor to detect nitrite. Cyclic voltammogram of DNA-CNTs/Cu(2+)/GCE showed a pair of well-defined redox peaks for Cu(2+)/Cu(+). Compared with DNA-CNTs/GCE and DNA-Cu(2+)/GCE, the prepared DNA-CNTs/Cu(2+)/GCE exhibited more excellent electrochemical properties. Thus, the prepared DNA-CNTs/Cu(2+)/GCE was proposed as nitrite sensor. The effects of Cu(2+), CNTs and DNA concentration in the mixture together with electrodeposition time and determination conditions such as applied potential, pH value on the current response of DNA-CNTs/Cu(2+)/GCE toward nitrite were optimized to obtain the maximal sensitivity. In addition, electrochemical experiments revealed that the modified electrode showed high electrocatalytic activity to the reduction of nitrite ion (NO(2)(-)). The linear range for the detection of NO(2)(-) was 3x10(-8) to 2.6x10(-3)M, and the response was very fast (less than 3s). A low detection limit of 3x10(-8)M (S/N=3) for NO(2)(-) was achieved.
authors.affiliation: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Hunan, Changsha 410082, PR China.
authors.forename: Shanli
authors.initials: S
authors.lastname: Yang
authors.forename: Binyuan
authors.initials: B
authors.lastname: Xia
authors.forename: Xiandong
authors.initials: X
authors.lastname: Zeng
authors.forename: Shenglian
authors.initials: S
authors.lastname: Luo
authors.forename: Wanzhi
authors.initials: W
authors.lastname: Wei
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Liu
mesh_terms: D002244:Carbon / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D004595:Electroplating / Q000379:methods; D006863:Hydrogen-Ion Concentration; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009573:Nitrites / Q000032:analysis*; D010084:Oxidation-Reduction
chemical_list: D037742:Nanotubes, Carbon; D009573:Nitrites; D002244:Carbon; D003300:Copper; D004247:DNA