Conjugated polymer-based DNA chip with real time access and femtomol detection threshold

被引:25
作者
Garnier, Francis
Bouabdallaoui, Benyounes
Srivastava, Pratima
Mandrand, Bernard
Chaix, Carole
机构
[1] Conservatoire Natl Arts & Metiers, Lab Genie Analyt, F-75003 Paris, France
[2] ENS Lyon, Unite Mixte, CNRS, Lyon, France
关键词
DNA chip; biosensor; ODN-functionalised polypyrrole; amplification mechanism; POLYPYRROLE; HYBRIDIZATION; RECOGNITION; GENOMICS; LENGTH;
D O I
10.1016/j.snb.2006.07.015
中图分类号
O65 [分析化学];
学科分类号
070302 ; 081704 ;
摘要
A multiplot DNA-biosensor has been realized on a plastic chip, by the controlled electropolymerization of a thin film of an electroactive pyrrolebased copolymer, poly [pyrrole-COOH, pyrrole-ODNprobe], onto eight gold microelectrodes deposited on the chip. The electrochemical signature of these polypyrrole films vary upon hybridisation of the grafted ODN probes with complementary ODN targets present in an aqueous analyte solution. This direct transduction of the recognition process into an electrical signal allows a real time access to the sensing process, bypassing the conventional tagging step required in other biosensors. It is shown that the key factor governing the detection threshold of these biosensors concerns the quantity of ODN probes deposited on the microelectrodes. By varying the pyrrole-ODN/pyrrole-COOH ratio in the film and by tuning it to the quantity of ODN targets present in the analyte solution, a detection threshold value of 2 x 10(-15) mol of ODN target in 2 mL hybridisation solution has been experimentally obtained. The discussion of this very low detection threshold led us to propose the existence of an amplification factor in the electrochemical response of a conjugated polymer-based (bio)sensor. (c) 2006 Elsevier B.V. All rights reserved.
引用
收藏
页码:13 / 20
页数:8
相关论文
共 30 条