Type

Journal Article

Authors

Robert J. Forster
Tia E. Keyes
Thomas Barry
Katrina Lacey
Justin O' Grady
Gordan G Wallace
Richard B Kaner
Robert Kojima
Elaine Spain

Subjects

Microbiology

Topics
isolation purification gold nanoparticles aniline compounds biosensing techniques chemistry equipment failure analysis polyaniline equipment design electrodes genetics conductometry staphylococcus aureus instrumentation dna bacterial

High sensitivity DNA detection using gold nanoparticle functionalised polyaniline nanofibres. (2010)

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(-6) mol L(-1) and pM concentrations could be detected without the need for molecular, e.g., PCR or NASBA, amplification.
Collections Ireland -> Dublin City University -> PubMed

Full list of authors on original publication

Robert J. Forster, Tia E. Keyes, Thomas Barry, Katrina Lacey, Justin O' Grady, Gordan G Wallace, Richard B Kaner, Robert Kojima, Elaine Spain

Experts in our system

1
Robert J. Forster
Dublin City University
Total Publications: 92
 
2
Tia E. Keyes
Dublin City University
Total Publications: 104
 
3
Thomas Barry
Dublin City University
Total Publications: 20
 
4
Elaine Spain
Dublin City University
Total Publications: 15