Versatile biosensors with signal amplification based on dynamic programming of DNA structure

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H03829
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Analytical chemistry
• Research Institution: Kumamoto University
• Principal Investigator: Ihara Toshihiro 熊本大学, 大学院先端科学研究部(工), 教授 (40253489)
• Co-Investigator(Kenkyū-buntansha): 吉本 惣一郎 熊本大学, 大学院先端科学研究部(工), 准教授 (30323067) ; 今堀 龍志 東京理科大学, 工学部工業化学科, 准教授 (90433515)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: DNAサーキット / HCR / 鎖交換反応 / 発光性希土類金属錯体 / フェロセン / シクロデキストリン / 電気化学 / シグナル増幅反応

Outline of Final Research Achievements

We have developed the signal amplification systems consisting of chemically-modified DNA conjugates. The luminescence and electrochemical signals were catalytically amplified with autonomous successive DNA strand exchanges such as HCR (hybridization chain reaction) and DNA circuits. The luminous signal amplification was performed with EDTA- and Phen (1,10-phenanthrorine)-modified DNA in the presence of lanthanide (Tb3+ or Eu3+) ion. The complexes formed on the certain DNA structures such as tandem duplex DNA, long tandem DNA wire, and cruciform DNA. Their luminescence lifetimes were extremely long as those of the typical luminous Ln complexes and their luminescence quantum yields were moderate, ca. 10 %. Electrochemical signals were amplified through entropy-driven DNA circuit consisting of Fc (ferrocene)- and βCyD (β-cyclodextrin)-modified DNA. We succeeded in enhancing the signals more by trapping Fc-DNA on the electrode modified with its complementary DNA.

Free Research Field

生物分析化学、核酸化学