Ultrasensitive DNA aptasensors based on exponential amplification reaction

Brown, Darius

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https://hdl.handle.net/2142/46916 Copy

Description

Title

Ultrasensitive DNA aptasensors based on exponential amplification reaction

Author(s)

Brown, Darius

Issue Date

2014-01-16T18:26:15Z

Director of Research (if dissertation) or Advisor (if thesis)

Lu, Yi

Department of Study

Chemistry

Discipline

Chemistry

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Aptasensor
• Cocaine
• Thrombin
• Exponential amplification reaction (EXPAR)
• Magnetic Beads
• Deoxyribonucleic acid (DNA)

Abstract

This is a comprehensive project for the development of a general method to enhance the sensitivity of DNA aptasensors by coupling them with an isothermal DNA amplification technique known as exponential amplification reaction (EXPAR). The method involves two steps: (1) first, the target-induced structure-switching of DNA aptamers causes the release of trigger oligonucleotides from the aptamers immobilized on a surface; (2) then, the released trigger oligonucleotides are amplified by the EXPAR technique for ultrasensitive detection. It is shown that the detection limit of a cocaine aptasensor is improved from 5 micromolar in assays without amplification to 0.8-1micromolar when EXPAR is applied, providing a 5-fold enhancement. The flexibility in designing the sequences of the trigger oligonucleotides enables the method generally applicable to other aptasensor systems such as thrombin aptamers. By EXPAR, the method has also achieved 10-fold enhancement in sensitivity from 4nM to 400 pM for thrombin detection, in comparison with similar assays without EXPAR.

Graduation Semester

2013-12

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http://hdl.handle.net/2142/46916

Copyright and License Information

Copyright 2013 Darius Z Brown

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