title: Selective detection of silver ions using mushroom-like polyaniline and gold nanoparticle nanocomposite-based electrochemical DNA sensor.
abstract: A highly sensitive electrochemical DNA biosensor made of polyaniline (PANI) and gold nanoparticles (AuNPs) nanocomposite (AuNPs@PANI) has been used for the detection of trace concentration of Ag(+). In the presence of Ag(+), with the interaction of cytosine-Ag(+)-cytosine (C-Ag(+)-C), cytosine-rich DNA sequence immobilized onto the surface of AuNPs@PANI has a self-hybridization and then forms a duplex-like structure. The whole detection procedure of Ag(+) based on the developed biosensor was evaluated by electrochemical impedance spectroscopy. On semi-logarithmic plots of the log Ag(+) concentration versus peak current, the results show that the prepared biosensor can detect silver ions at a wide linear range of 0.01-100 nM (R = 0.9828) with a detection limit of 10 pM (signal/noise = 3). Moreover, the fabricated sensor exhibits good selectivity and repeatability. The detection of Ag(+) was determined by Ag(+) self-induced conformational change of DNA scaffold that involved only one oligonucleotide, showing its convenience and availability.
authors: Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China; Henan Provincial Key Laboratory of Surface and Interface Science, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China.
authors: Yanqin
authors: Y
authors: Yang
authors: Henan Provincial Key Laboratory of Surface and Interface Science, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China.
authors: Shuai
authors: S
authors: Zhang
authors: Henan Provincial Key Laboratory of Surface and Interface Science, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China.
authors: Mengmeng
authors: M
authors: Kang
authors: Henan Provincial Key Laboratory of Surface and Interface Science, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China.
authors: Linghao
authors: L
authors: He
authors: Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China; Henan Provincial Key Laboratory of Surface and Interface Science, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China.
authors: Jihong
authors: J
authors: Zhao
authors: Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China; Henan Provincial Key Laboratory of Surface and Interface Science, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China.
authors: Hongzhong
authors: H
authors: Zhang
authors: Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China; Henan Provincial Key Laboratory of Surface and Interface Science, Zhengzhou University of Light Industry, No. 166, Zhengzhou 450001, China. Electronic address: mainzhh@163.com.
authors: Zhihong
authors: Z
authors: Zhang
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry; D015374:Biosensing Techniques; D002681:China; D003596:Cytosine / Q000737:chemistry; D004277:DNA, Single-Stranded / Q000737:chemistry*; D017097:Electric Impedance; D061925:Immobilized Nucleic Acids / Q000737:chemistry*; D007202:Indicators and Reagents / Q000032:analysis; D017736:Ion-Selective Electrodes; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D009994:Osmolar Concentration; D015203:Reproducibility of Results; D012834:Silver / Q000032:analysis*; D013499:Surface Properties; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000814:Aniline Compounds; D004277:DNA, Single-Stranded; D061925:Immobilized Nucleic Acids; D007202:Indicators and Reagents; D014874:Water Pollutants, Chemical; C416807:polyaniline; D012834:Silver; D003596:Cytosine
keywords: AuNPs@PANI; Detection of silver ions; Electrochemical biosensor; Electrochemical impedance spectroscopy