A highly sensitive, label-free gene sensor based on a single conducting polymer nanowire.

A prerequisite for exploiting sensing devices based on semiconductor nanowires is ultra-sensitive and selective direct electrical detection of biological and chemical species. Here, we constructed a transducer based on copolymer of poly(3,4,-ethylenedioxythiophene) (PEDOT) and carboxylic group functionalised PEDOT single nanowire in between gold electrodes, followed by covalent attachment of amino-modified probe oligonucleotide. The target ODNs specific to Homo sapiens Breast and ovarian cancer cells were detected at femtomolar concentration and incorporation of negative controls (non-complementary ODN) were clearly discriminated by the sensor. The ex situ measurements were performed by using two terminal device setup and the changes in the interface of the nanowire associated with the association or dissociation of ODNs were measured as change in resistance. In addition, in situ measurements were performed by utilizing scanning ion conductance microscopy to measure the change in resistance of probe modified nanowire upon addition of different concentration of target ODNs in presence of relevant buffer. The constructed, nano sensor showed highly sensitive concentration dependent resistance change.

[1]  Zhiqiang Gao,et al.  Nanostructure-based electrical biosensors , 2009 .

[2]  D. Grischkowsky,et al.  Single-step growth and low resistance interconnecting of gold nanowires , 2007 .

[3]  Ashok Mulchandani,et al.  Single Conducting Polymer Nanowire Based Sequence‐Specific, Base‐Pair‐Length Dependant Label‐free DNA Sensor , 2011 .

[4]  Jun Kameoka,et al.  Polymeric Nanowire Chemical Sensor , 2004 .

[5]  Christian Soeller,et al.  Novel Conducting Polymers for DNA Sensing , 2007 .

[6]  Emril Mohamed Ali,et al.  Conductivity Shift of Polyethylenedioxythiophenes in Aqueous Solutions from Side-Chain Charge Perturbation , 2007 .

[7]  Jiri Janata,et al.  Principles of Chemical Sensors , 1989 .

[8]  M. Mayor,et al.  Two-dimensional assembly and local redox-activity of molecular hybrid structures in an electrochemical environment. , 2006, Faraday discussions.

[9]  David E. Williams,et al.  Measuring the ionic flux of an electrochemically actuated conducting polymer using modified scanning ion conductance microscopy. , 2011, Journal of the American Chemical Society.

[10]  G. Weiss,et al.  Virus-PEDOT nanowires for biosensing. , 2010, Nano letters.

[11]  C. Lieber,et al.  Nanowire Nanosensors for Highly Sensitive and Selective Detection of Biological and Chemical Species , 2001, Science.

[12]  J. Ying,et al.  Poly(3,4-ethylenedioxythiophene) (PEDOT) nanobiointerfaces: thin, ultrasmooth, and functionalized PEDOT films with in vitro and in vivo biocompatibility. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[13]  H. Xie,et al.  Electric-field-assisted growth of functionalized poly(3,4-ethylenedioxythiophene) nanowires for label-free protein detection. , 2009, Small.

[14]  Steven E. Bayer,et al.  A strong candidate for the breast and ovarian cancer susceptibility gene BRCA1. , 1994, Science.

[15]  Lin Xu,et al.  Single nanowire electrochemical devices. , 2010, Nano letters.

[16]  Yuyuan Tian,et al.  Controlling charge transport in single molecules using electrochemical gate. , 2006, Faraday discussions.

[17]  D. Grischkowsky,et al.  Directional growth of metallic and polymeric nanowires , 2009, Nanotechnology.

[18]  Fu-Hsiang Ko,et al.  Label-free biosensing of a gene mutation using a silicon nanowire field-effect transistor. , 2009, Biosensors & bioelectronics.

[19]  Ashok Mulchandani,et al.  Single conducting polymer nanowire chemiresistive label-free immunosensor for cancer biomarker. , 2009, Analytical chemistry.

[20]  S. Morrison.  Electrochemistry at Semiconductor and Oxidized Metal Electrodes , 1980 .

[21]  D. Klenerman,et al.  Nanoscale live-cell imaging using hopping probe ion conductance microscopy , 2009, Nature Methods.

[22]  Suxian Huang,et al.  Ultrasensitive fluorescence detection of single protein molecules manipulated electrically on Au nanowire. , 2008, Nano letters.

[23]  N Balasubramanian,et al.  DNA sensing by silicon nanowire: charge layer distance dependence. , 2008, Nano letters.

[24]  C. Nuckolls,et al.  A molecular switch based on potential-induced changes of oxidation state. , 2005, Nano letters.

[25]  M. Bangar,et al.  Conducting polymer nanowire-based chemiresistive biosensor for the detection of bacterial spores. , 2010, Biosensors & bioelectronics.

[26]  David E. Williams,et al.  High-sensitivity, label-free DNA sensors using electrochemically active conducting polymers. , 2011, Analytical chemistry.

[27]  David E. Williams,et al.  The electrochemical growth of conducting polymer “nanowires” , 2012 .

[28]  Gengfeng Zheng,et al.  Fabrication of silicon nanowire devices for ultrasensitive, label-free, real-time detection of biological and chemical species , 2006, Nature Protocols.

[29]  Xuema Li,et al.  Sequence-Specific Label-Free DNA Sensors Based on Silicon Nanowires , 2004 .

[30]  C. Soeller,et al.  Conducting polymers for electrochemical DNA sensing. , 2009, Biomaterials.

[31]  Charles M. Lieber,et al.  Direct ultrasensitive electrical detection of DNA and DNA sequence variations using nanowire nanosensors , 2004 .

[32]  Gengfeng Zheng,et al.  Electrical detection of single viruses. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[33]  P. Hansma,et al.  The scanning ion-conductance microscope. , 1989, Science.

[34]  Anil Kumar,et al.  Novel label-free DNA sensors based on poly(3,4-ethylenedioxythiophene). , 2004, Chemical communications.

[35]  Joseph Irudayaraj,et al.  PCR-free quantification of multiple splice variants in a cancer gene by surface-enhanced Raman spectroscopy. , 2009, The journal of physical chemistry. B.