A DNA biosensor based on the detection of doxorubicin-conjugated Ag nanoparticle labels using solid-state voltammetry

作者：Ting Boon Ping; Zhang Jie; Gao Zhiqiang; Ying Jackie Y^*

来源：Biosensors and Bioelectronics, 2009, 25(2): 282-287.

DOI：10.1016/j.bios.2009.07.005

• Flu virus H5N1
• DNA biosensor
• Electrochemistry
• Silver nanoparticle labels
• Solid-state voltammetry
• Doxorubicin

This report describes an electrochemical biosensor for the detection of short DNA oligonucleotide of the avian flu virus H5N1 with sequence 5'-CCA AGC AAC AGA CTC AAA-T. To fabricate this DNA biosensor, a gold (Au) electrode surface was modified with thiolated DNA probes with a sequence complementary to the target DNA. This modified Au electrode was incubated in a buffer solution containing the target DNA to form double-stranded DNA (ds-DNA) through hybridization. The ds-DNA on the electrode surface was then labeled with silver nanoparticles conjugated with a well-known DNA intercalator, doxorubicin. By performing cyclic voltammetry in an aqueous KCl solution (0.3 M), the silver nanoparticle labels were detected as a result of the highly characteristic solid-state Ag/AgCl redox process. The signal obtained was subsequently used to quantify the amount of DNA. A detection limit of 1 pM has been achieved with this new DNA biosensor.

• 出版日期2009-10-15