Nanostructured platform for the detection of Neisseria gonorrhoeae using electrochemical impedance spectroscopy and differential pulse voltammetry

Abstract

We report on a nanocomposite based genosensor for the detection of Neisseria gonorrhoeae, a bacterium causing the sexually transmitted disease gonorrhoea. Aminolabeled probe DNA was covalently immobilized on electrochemically prepared polyaniline and iron oxide (PANI-Fe 3 O 4 ) nanocomposite film on an indium tin oxide (ITO) electrode. Scanning electron microscopy, transmission electron microscopy, electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) techniques have been employed to characterize surface of the modified electrode. The genosensor has detection limits of 1 ×10 -15 M and 1×10 -17 M, respectively, using the EIS and DPV techniques.This biosensor can discriminate a complementary sequence from a single-base mismatch and from non-complementary DNA, and has been utilized for detection of DNA extracted from N. gonorrhoeae culture, and from patient samples with N. gonorrhoeae. It is found to exhibit good specificity for N. gonorrhoeae species and shows no response towards nongonorrhoeae type of Neisseria species (NgNs) and other gram-negative bacterias (GNBs). The affinity constant for hybridization calculated using the Langmuir adsorption isotherm model is found to be 3.39×10 8 M -1 .

Electrochemical impedance spectroscopy: an overview of bioanalytical applications

“…91 Comparably, the total impedance was found to be larger than when the electrode was immersed in K. Pneumoniae, S. Aureus, E. Coli or N. Sicca. 91 This work suggests that graphene related composites could be utilised to create miniaturised sensing platforms to selectively detect different strains of bacteria and (hopefully) concentration levels. It is an exciting prospect to think that disease could be diagnosed on-the-spot instead of taking extended periods of time by sending samples to labs and using time consuming techniques such as PCR and ELISA.…”

“…Further recent advances in graphene technology carry on with the theme of sexually transmitted diseases, and concern the electrochemical detection of the Neisseria gonorrhoea bacterium which is responsible for the sexually transmitted disease gonorrhoea. 91 A chemically prepared polyaniline and iron oxide nanocomposite is deposited upon an indium tin oxide electrode in the work by Singh et al which, upon addition of an amino labelled DNA probe, selectively exhibited an increased charge transfer resistance when immersed in a solution of complimentary DNA taken from gonorrhoea bacteria. 91 Comparably, the total impedance was found to be larger than when the electrode was immersed in K. Pneumoniae, S. Aureus, E. Coli or N. Sicca.…”

“…91 A chemically prepared polyaniline and iron oxide nanocomposite is deposited upon an indium tin oxide electrode in the work by Singh et al which, upon addition of an amino labelled DNA probe, selectively exhibited an increased charge transfer resistance when immersed in a solution of complimentary DNA taken from gonorrhoea bacteria. 91 Comparably, the total impedance was found to be larger than when the electrode was immersed in K. Pneumoniae, S. Aureus, E. Coli or N. Sicca. 91 This work suggests that graphene related composites could be utilised to create miniaturised sensing platforms to selectively detect different strains of bacteria and (hopefully) concentration levels.…”

Recent progress and challenges on the bioassay of pathogenic bacteria

“…The fabricated genosensor applied for, and patient specimens bacterial culture of N.gonorrhoeae for determination of DNA extracted. The results showed that the LOD was1 × 10 −15 M and 1 × 10 −17 M 103 …”

“…For complete of discussion, Table 2 25‐206 summarized all of the discussed articles on the detection of bacterial. It is important to point out that, there is other reports in this research area …”