A new electrochemical biosensor of host-guest recognition mode for DNA hybridization detection

作者：Zhao Hui; Fan Hao^*; Ceng Jinxiang; Li Qianggen; Lin Yan; Wang Xiaoyun

来源：Journal of New Materials for Electrochemical Systems, 2012, 15(1).

• DNA hybridization detection
• Double stranded DNA
• Electrochemical
• Electrochemical biosensor
• Electrochemical measurements
• Electrode surfaces
• Glassy carbon electrodes
• Guest molecules
• Host-guests
• Stem-loop structures

This paper reports on an electrochemical biosensor to detect the hybridization specificity by using host-guest recognition technique. A hairpin DNA with a dabcyl molecule which is typical guest molecule toβ- Cyclodextrins (β-CD) at the 3′-terminus and a NH2 linked at the 5′-terminus as the probe DNA. The probe DNA was immobilized on the PdS nanoparticle to construct a double-labeled probe (DLP) and could selectively hybridize with its target DNA. Aβ-CD modified Poly(N-acetylaniline) glassy carbon electrode was used for capturing dabcyl in DLP. Without binding with target DNA, the DLP keep stem-loop structure and block dabcyl enter into the cavity of β-CD on electrode. However, a target-binding DLP is incorporated into double stranded DNA, causing loop-stem structure opened and dabcyl could be easy captured by β-CD which brought DLP on electrode surface. With electrochemical measurement, the signal come from Pd2+ be used for target DNA quantitative analysis.