title: Magnesium oxide grafted carbon nanotubes based impedimetric genosensor for biomedical application.
abstract: Nanostructured magnesium oxide (size<10nm) grafted carboxyl (COOH) functionalized multi-walled carbon nanotubes (nMgO-cMWCNTs) deposited electrophoretically onto indium tin oxide (ITO) coated glass electrode and have been utilized for Vibrio cholerae detection. Aminated 23 bases single stranded DNA (NH2-ssDNA) probe sequence (O1 gene) of V. cholerae has been covalently functionalized onto nMgO-cMWCNTs/ITO electrode surface using EDC-NHS chemistry. This DNA functionalized MgO grafted cMWCNTs electrode has been characterized using X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical techniques. The results of XPS studies reveal that sufficient O-C=O groups present at the nMgO-cMWCNTs surface are utilized for DNA binding. The results of hybridization studies conducted with fragmented target DNA (ftDNA) of V. cholerae using electrochemical impedance spectroscopy (EIS) reveal sensitivity as 3.87 Ω ng(-1) cm(-2), detection limit of ~21.70 ng µL(-1) in the linear range of 100-500 ng µL(-1) and stability of about 120 days. The proposed DNA functionalized nMgO-cMWCNTs nanomatrix provides a novel impedimetric platform for the fabrication of a compact genosensor device for biomedical application.
authors.affiliation: Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi 110012, India; Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India.
authors.forename: Manoj Kumar
authors.initials: MK
authors.lastname: Patel
authors.forename: Md Azahar
authors.initials: MA
authors.lastname: Ali
authors.forename: Saurabh
authors.initials: S
authors.lastname: Srivastava
authors.forename: Ved Varun
authors.initials: VV
authors.lastname: Agrawal
authors.forename: S G
authors.initials: SG
authors.lastname: Ansari
authors.forename: Bansi D
authors.initials: BD
authors.lastname: Malhotra
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004269:DNA, Bacterial / Q000032:analysis; D004277:DNA, Single-Stranded / Q000032:analysis; D058266:Dielectric Spectroscopy / Q000295:instrumentation*; D004867:Equipment Design; D057230:Limit of Detection; D008277:Magnesium Oxide / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D014734:Vibrio cholerae / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D004269:DNA, Bacterial; D004277:DNA, Single-Stranded; D037742:Nanotubes, Carbon; D008277:Magnesium Oxide
keywords: DNA functionalization; Genosensor; Impedance spectroscopy; Magnesium oxide; Multi-walled carbon nanotubes; Vibrio cholerae