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Article
Aptamer Functionalized Microcantilever Sensors for Cocaine Detection
Langmuir
  • Kyungho Kang, Iowa State University
  • Ashish Sachan, Iowa State University
  • Marit Nilsen-Hamilton, Iowa State University
  • Pranav Shrotriya, Iowa State University
Document Type
Article
Publication Version
Published Version
Publication Date
1-1-2011
DOI
10.1021/la202067y
Abstract
A cocaine-specific aptamer was used as a receptor molecule in a microcantilever-based surface stress sensor for detection of cocaine molecules. An interferometric technique that relies on measuring differential displacement between two microcantilevers (a sensing/reference pair) was utilized to measure the cocaine/aptamer binding induced surface stress changes. Sensing experiments were performed for different concentrations of cocaine from 25 to 500 μM in order to determine the sensor response as a function of cocaine concentration. In the lower concentration range from 25 to 100 μM, surface stress values increased proportionally to coverage of aptamer/cocaine complexes from 11 to 26 mN/m. However, as the cocaine concentration was increased beyond 100 μM, the surface stress values demonstrated a weaker dependence on the affinity complex surface coverage. On the basis of a sensitivity of 3 mN/m for the surface stress measurement, the lowest detectable threshold for the cocaine concentration is estimated to be 5 μM. Sensing cantilevers could be regenerated and reused because of reversible thermal denaturation of aptamer.
Comments

Reprinted (adapted) with permission from Langmuir, 2011, 27 (23), pp 14696–14702, doi:10.1021/la202067y. Copyright 2011 American Chemical Society.

Copyright Owner
American Chemical Society
Language
en
File Format
application/pdf
Citation Information
Kyungho Kang, Ashish Sachan, Marit Nilsen-Hamilton and Pranav Shrotriya. "Aptamer Functionalized Microcantilever Sensors for Cocaine Detection" Langmuir Vol. 27 Iss. 23 (2011) p. 14696 - 14702
Available at: http://works.bepress.com/marit-nilsen-hamilton/9/