An Nb-doped Nickel Oxide-Carbon Nanotubes Composite-Enhanced Electrochemical DNA Biosensor for Detection of Lead(II) Ion

作者：Chen, Daiwu^*; Deng, Fenfang; Ding, Cong; Wang, Yu; Li, He

来源：International Journal of Electrochemical Science, 2015, 10(11): 9015-9027.

• Niobium doped nickel oxide
• Electrochemical DNA biosensor
• Lead (II) ion

A novel niobium doped nickel oxide nanoparticle (NbNiO) was synthesized by sol-gel method and was applied to fabricate DNA biosensor for detection of Pb2+ in water sample for the first time. The amino-modified G-rich DNA probes were immobilized on the surface of CH-NbNiO-MWCNTs/ITO electrode by the covalent interaction between the amino of DNA and the carboxyl of MWCNTs. When the lead (II) ion (Pb2+) interacted with the G-rich DNA, it will induce the DNA conformational to switch from a random-coil to a G-quadruplex resulting in an increase of alternating current impedance. On the basis of this, we developed an impedance biosensor for the detection of Pb2+. The results showed that the synergistic effect of the synthesized NbNiO nanoparticles and MWCNs could improve the performance of this DNA biosensor. Under optimal conditions, the fabricated DNA biosensor possess a wide linear range of 1.0x10(-10) to 1.0x10(-5) M (correlation coefficient, R=0.998) and a low detection limit of 7.51 x10(-12) M (3 sigma).

• 出版日期2015-11
• 单位南方医科大学; 华南师范大学