Disposable Electrochemical Biosensor with Multiwalled Carbon Nanotubes-Chitosan Composite Layer for the Detection of Deep DNA Damage

Abstract

A novel electrochemical DNA-based biosensor for the detection of deep DNA damage was designed employing the bionanocomposite layer of multiwalled carbon nanotubes (MWNT) in chitosan (CHIT) deposited on a screen printed carbon electrode (SPCE). The biocomponent represented by double-stranded (ds) herring sperm DNA was immobilized on this composite using layer-by-layer coverage to form a robust film. Individual and complex electrode modifiers are characterized by a differential pulse voltammetry (DPV) with the DNA redox marker [Co(phen)3] 3+ , cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) with [Fe(CN)6] 3-as a redox probe in a phosphate buffer solution (PBS). A good correlation between the CV and EIS parameters has been found, thus confirming a strong effect of MWNT on the enhancement of the electroconductivity of the electrode surface and that of CHIT on the MWNT distribution at the electrode surface. Differences between the CV and EIS signals of the electrodes without and with DNA are used to detect deep damage to DNA, advantageously using simple working procedures in the same experiment.

Investigation of a DNA‐Based Biosensor with Chitosan‐Carbon Nanotubes Interface by Cyclic and Elimination Voltammetry

“…The parameters obtained from TPA are summarized in Table 3 considering the geometry of the electrode. The polarization (electron transfer) resistance (R Pcat and R Pan values) at various modified surfaces shows a similar shift to each other as that obtained previously by electrochemical impedance spectroscopy (EIS) [54]. The R P can be used a quantitative parameter to compare the resistance of electrode surface under various conditions.…”

Nanobiotechnology in Agricultural Development

“…For effective discrimination of DNA sequences, MWNTs/ZnO/CHIT composite fi lm-modifi ed GCE has been used for immobilization of ssDNA probes (Zhang et al 2008a , b ). To detect deep DNA damage, bionanocomposite layer of multiwalled nanotube is deposited on SPCE in chitosan (Galandova et al 2008 ). Nano-SiO 2 thiophenol/p-amino fi lm (PATP) is used to detect PAT gene sequences by a label-free EIS method (Ma et al 2008 ).…”

Electrochemical nucleic acid-based biosensors: Concepts, terms, and methodology (IUPAC Technical Report)

“…Using peptide nucleic probe (bearing no negative charge) offers a better discrimination between the (uncharged) probe and the (negatively charged PNAؒDNA) hybrid. Redox indicators such as the anionic complex hexacyanoferrate (III/II), [Fe(CN) 6 ] 3-/4-, (being repelled from the DNA-modified surface) or the cationic complex [Ru(NH 3 ) 6 ] 3+/2+ (being attracted to the negatively charged hybrids) have been employed to monitor changes in the negative charge density using impedimetric or voltammetric techniques as well as scanning electrochemical microscopy [17,19,20].…”