title: Bioaffinity sensing using biologically functionalized conducting-polymer nanowire.
abstract: A simple, one-step method for fabricating single biologically functionalized conducting-polymer (polypyrrole) nanowire on prepatterned electrodes and its application to biosensing was demonstrated. The biologically functionalized polypyrrole was formed by the electropolymerization of an aqueous solution of pyrrole monomer and the model biomolecule, avidin- or streptavidin-conjugated ZnSe/CdSe quantum dots, within 100 or 200 nm wide by 3 mum long channels between gold electrodes on prefabricated silicon substrate. When challenged with biotin-DNA, the avidin- and streptavidin-polypyrrole nanowires generated a rapid change in resistance to as low as 1 nM, demonstrating the utility of the biomolecule-functionalized nanowire as biosensor. The method offers advantages of direct incorporation of functional biological molecules into the conducting-polymer nanowire during its synthesis, site-specific positioning, built-in electrical contacts, and scalability to high-density nanoarrays over the reported silicon nanowire and carbon nanotube biosensors.
authors.affiliation: Department of Chemical and Environmental Engineering, and Center for Nanoscale Science and Engineering, University of California-Riverside, Riverside, California 92521, USA.
authors.forename: Kumaran
authors.initials: K
authors.lastname: Ramanathan
authors.forename: Mangesh A
authors.initials: MA
authors.lastname: Bangar
authors.forename: Minhee
authors.initials: M
authors.lastname: Yun
authors.forename: Wilfred
authors.initials: W
authors.lastname: Chen
authors.forename: Nosang V
authors.initials: NV
authors.lastname: Myung
authors.forename: Ashok
authors.initials: A
authors.lastname: Mulchandani
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D001710:Biotin / Q000737:chemistry; D019187:Cadmium Compounds / Q000737:chemistry*; D004247:DNA / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D010455:Peptides / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D018036:Selenium Compounds / Q000737:chemistry*; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D010455:Peptides; D011108:Polymers; D011758:Pyrroles; D018036:Selenium Compounds; D017967:Zinc Compounds; C019529:polyalanine; C067635:polypyrrole; D001710:Biotin; D004247:DNA; C058667:cadmium selenide; C044696:zinc selenide