title: Virtual electrochemical nitric oxide analyzer using copper, zinc superoxide dismutase immobilized on carbon nanotubes in polypyrrole matrix.
abstract: In this work, we have designed and developed a novel and cost effective virtual electrochemical analyzer for the measurement of NO in exhaled breath and from hydrogen peroxide stimulated endothelial cells using home-made potentiostat. Here, data acquisition system (NI MyDAQ) was used to acquire the data from the electrochemical oxidation of NO mediated by copper, zinc superoxide dismutase (Cu,ZnSOD). The electrochemical control programs (graphical user-interface software) were developed using LabVIEW 10.0 to sweep the potential, acquire the current response and process the acquired current signal. The Cu,ZnSOD (SOD1) immobilized on the carbon nanotubes in polypyrrole modified platinum electrode was used as the NO biosensor. The electrochemical behavior of the SOD1 modified electrode exhibited the characteristic quasi-reversible redox peak at the potential, +0.06 V vs. Ag/AgCl. The biological interferences were eliminated by nafion coated SOD1 electrode and then NO was measured selectively. Further, this biosensor showed a wide linear range of response over the concentration of NO from 0.1 μM to 1 mM with a detection limit of 0.1 μM and high sensitivity of 1.1 μA μM(-1). The electroanalytical results obtained here using the developed virtual electrochemical instrument were also compared with the standard cyclic voltammetry instrument and found in agreement with each other.
authors.affiliation: Biomedical Research Laboratory, Department of Chemistry, VHNSN College, Virudhunagar 626 001, Tamil Nadu, India.
authors.forename: Thangamuthu
authors.initials: T
authors.lastname: Madasamy
authors.forename: Manickam
authors.initials: M
authors.lastname: Pandiaraj
authors.forename: Murugesan
authors.initials: M
authors.lastname: Balamurugan
authors.forename: Santosh
authors.initials: S
authors.lastname: Karnewar
authors.forename: Alby Robson
authors.initials: AR
authors.lastname: Benjamin
authors.forename: Krishna Arun
authors.initials: KA
authors.lastname: Venkatesh
authors.forename: Kanagavel
authors.initials: K
authors.lastname: Vairamani
authors.forename: Srigiridhar
authors.initials: S
authors.lastname: Kotamraju
authors.forename: Chandran
authors.initials: C
authors.lastname: Karunakaran
mesh_terms: D000328:Adult; D015374:Biosensing Techniques / Q000379:methods*; D001944:Breath Tests; D004563:Electrochemistry; D004566:Electrodes; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D045853:Exhalation; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009569:Nitric Oxide / Q000378:metabolism*; D010984:Platinum / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011381:Programming Languages; D011758:Pyrroles / Q000737:chemistry*; D013482:Superoxide Dismutase / Q000737:chemistry* / Q000378:metabolism
chemical_list: D004800:Enzymes, Immobilized; D037742:Nanotubes, Carbon; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D009569:Nitric Oxide; D010984:Platinum; D006861:Hydrogen Peroxide; D013482:Superoxide Dismutase