Hybridization chain reaction and gold nanoparticles dual signal amplification for sensitive glucose detection

作者：Li, Zongbing; Miao, Xiangmin^*; Zhu, Aihua; Ling, Liansheng

来源：Biochemical Engineering Journal, 2015, 103: 205-210.

DOI：10.1016/j.bej.2015.08.001

• Electrochemical sensor
• Glucose detection
• Hybridization chain reaction
• Positively charged gold nanoparticles
• Ferrocene
• DNA hairpins

Ultrasensitive electrochemical method was established for glucose detection coupling hybridization chain reaction (HCR) and positively charged gold nanoparticles ((+)AuNPs) dual signal amplification. Molecular beacon (MB) was initially assembled onto gold electrode surface in their folded states. Hybridization of MB with detection probe opened the stem-loop structure of it, then another exposed part of it opened two ferrocene (Fc) modified DNA hairpins (H-1 and H-2) and induced HCR, which produced a strong current signal due to the formation of numerous Fc on such double-helix. Meantime, (+)AuNPs were electrostatically adsorbed onto such double-helix to amplify electrochemical signal. However, if the detection probe was incubated with the mixture of glucose, glucose oxidase (GOD) and Fe2+ firstly, it would be cleaved into DNA fragments and could not open the stem-loop structure of MB, accordingly resulted in no HCR happen and (+)AuNPs adsorption. Upon optimal conditions, a low detection limit of 21 pM for glucose detection was obtained. Moreover, the practicability of the assay in glucose detection of human serums was studied as well.

• 出版日期2015-11-15
• 单位中山大学