title: Rapid detection of ssDNA and RNA using multi-walled carbon nanotubes modified screen-printed carbon electrode.
abstract: A method for rapid sensitive detection of DNA or RNA was designed using a composite screen-printed carbon electrode modified with multi-walled carbon nanotubes (MWNTs). MWNTs showed catalytic characteristics for the direct electrochemical oxidation of guanine or adenine residues of signal strand DNA (ssDNA) and adenine residues of RNA, leading to indicator-free detection of ssDNA and RNA concentrations. With an accumulation time of 5 min, the proposed method could be used for detection of calf thymus ssDNA ranging from 17.0 to 345 microg ml(-1) with a detection limit of 2.0 microg ml(-1) at 3 sigma and yeast tRNA ranging from 8.2 microg ml(-1) to 4.1 mg ml(-1). AC impedance was employed to characterize the surface of modified electrodes. The advantages of convenient fabrication, low-cost detection, short analysis time and combination with nanotechnology for increasing the sensitivity made the subject worthy of special emphasis in the research programs and sources of new commercial products.
authors.affiliation: Department of Chemistry, Institute of Analytical Science, Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing 210093, PR China.
authors.forename: Yongkang
authors.initials: Y
authors.lastname: Ye
authors.forename: Huangxian
authors.initials: H
authors.lastname: Ju
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D003199:Computer Systems; D004247:DNA / Q000032:analysis* / Q000737:chemistry; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008839:Microelectrodes; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D011327:Printing / Q000379:methods; D012343:RNA, Transfer / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012680:Sensitivity and Specificity
chemical_list: D001672:Biocompatible Materials; D037742:Nanotubes, Carbon; D004247:DNA; D012343:RNA, Transfer; C427203:calf thymus DNA