Label-free detection of DNA hybridization based on a novel functionalized conducting polymer.
A new functionalized pyrrole monomer, 3-pyrrolylacrylic acid (PAA) was synthesized. It was used to prepare a copolymer with pyrrole, poly(Py-co-PAA), which was investigated by reflective FT-IR, UV-vis spectroscopy and cyclic voltammetry. A label-free DNA sensor was prepared based on a poly(Py-co-PAA) film. Hybridization with complementary and non-complementary DNA targets was studied by electrochemical impedance spectroscopy. Results show a significant increase in the charge-transfer resistance upon addition of complementary target. The impedance spectra were analyzed by using a modified Randles and Ershler equivalent circuit model. The change in charge-transfer resistance that was used as an index of sensor response was found to be linear with logarithmic target concentration in the range of 2 x 10(-9) to 2 x 10(-7)M. The detection limit was 0.98 nM.
Peng
Hui
H
Polymer Electronics Research Centre, The University of Auckland, Private Bag 92019, Auckland, New Zealand. h.peng@auckland.ac.nz
Soeller
Christian
C
Vigar
Nicholas A
NA
Caprio
Vittorio
V
Travas-Sejdic
Jadranka
J
D004247:DNA / Q000032:analysis* / Q000378:metabolism; D015342:DNA Probes; D017097:Electric Impedance; D004563:Electrochemistry; D009693:Nucleic Acid Hybridization; D011108:Polymers / Q000737:chemistry; D011758:Pyrroles / Q000737:chemistry
D015342:DNA Probes; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; D004247:DNA