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High sensitivity DNA detection using gold nanoparticle functionalised polyaniline nanofibres

Journal Article


Abstract


  • Polyaniline (PANI) nanofibres (PANI-NF) have been modified with chemically grown gold nanoparticles to give a nanocomposite material (PANI-NF-AuNP) and deposited on gold electrodes. Single stranded capture DNA was then bound to the gold nanoparticles and the underlying gold electrode and allowed to hybridise with a complementary target strand that is uniquely associated with the pathogen, Staphylococcus aureus (S. aureus), that causes mastitis. Significantly, cyclic voltammetry demonstrates that deposition of the gold nanoparticles increases the area available for DNA immobilisation by a factor of approximately 4. EPR reveals that the addition of the Au nanoparticles efficiently decreases the interactions between adjacent PANI chains and/or motional broadening. Finally, a second horseradish peroxidase (HRP) labelled DNA strand hybridises with the target allowing the concentration of the target DNA to be detected by monitoring the reduction of a hydroquinone mediator in solution. The sensors have a wide dynamic range, excellent ability to discriminate DNA mismatches and a high sensitivity. Semi-log plots of the pathogen DNA concentration vs. faradaic current were linear from 150×10 -12 to 1×10 -6molL -1 and pM concentrations could be detected without the need for molecular, e.g., PCR or NASBA, amplification. © 2010 Elsevier B.V.

Authors


  •   Spain, E (external author)
  •   Kojima, R (external author)
  •   Kaner, Richard B. (external author)
  •   Wallace, Gordon G.
  •   O'Grady, J (external author)
  •   Lacey, K (external author)
  •   Barry, T (external author)
  •   Keyes, T E. (external author)
  •   Forster, R J. (external author)

Publication Date


  • 2011

Citation


  • Spain, E., Kojima, R., Kaner, R., Wallace, G. G., O'Grady, J., Lacey, K., Barry, T., Keyes, T. E. & Forster, R. J. (2011). High sensitivity DNA detection using gold nanoparticle functionalised polyaniline nanofibres. Biosensors and Bioelectronics, 26 (5), 2613-2618.

Scopus Eid


  • 2-s2.0-78650613865

Ro Metadata Url


  • http://ro.uow.edu.au/aiimpapers/444

Has Global Citation Frequency


Number Of Pages


  • 5

Start Page


  • 2613

End Page


  • 2618

Volume


  • 26

Issue


  • 5

Place Of Publication


  • Netherlands

Abstract


  • Polyaniline (PANI) nanofibres (PANI-NF) have been modified with chemically grown gold nanoparticles to give a nanocomposite material (PANI-NF-AuNP) and deposited on gold electrodes. Single stranded capture DNA was then bound to the gold nanoparticles and the underlying gold electrode and allowed to hybridise with a complementary target strand that is uniquely associated with the pathogen, Staphylococcus aureus (S. aureus), that causes mastitis. Significantly, cyclic voltammetry demonstrates that deposition of the gold nanoparticles increases the area available for DNA immobilisation by a factor of approximately 4. EPR reveals that the addition of the Au nanoparticles efficiently decreases the interactions between adjacent PANI chains and/or motional broadening. Finally, a second horseradish peroxidase (HRP) labelled DNA strand hybridises with the target allowing the concentration of the target DNA to be detected by monitoring the reduction of a hydroquinone mediator in solution. The sensors have a wide dynamic range, excellent ability to discriminate DNA mismatches and a high sensitivity. Semi-log plots of the pathogen DNA concentration vs. faradaic current were linear from 150×10 -12 to 1×10 -6molL -1 and pM concentrations could be detected without the need for molecular, e.g., PCR or NASBA, amplification. © 2010 Elsevier B.V.

Authors


  •   Spain, E (external author)
  •   Kojima, R (external author)
  •   Kaner, Richard B. (external author)
  •   Wallace, Gordon G.
  •   O'Grady, J (external author)
  •   Lacey, K (external author)
  •   Barry, T (external author)
  •   Keyes, T E. (external author)
  •   Forster, R J. (external author)

Publication Date


  • 2011

Citation


  • Spain, E., Kojima, R., Kaner, R., Wallace, G. G., O'Grady, J., Lacey, K., Barry, T., Keyes, T. E. & Forster, R. J. (2011). High sensitivity DNA detection using gold nanoparticle functionalised polyaniline nanofibres. Biosensors and Bioelectronics, 26 (5), 2613-2618.

Scopus Eid


  • 2-s2.0-78650613865

Ro Metadata Url


  • http://ro.uow.edu.au/aiimpapers/444

Has Global Citation Frequency


Number Of Pages


  • 5

Start Page


  • 2613

End Page


  • 2618

Volume


  • 26

Issue


  • 5

Place Of Publication


  • Netherlands