Microbiosensor for Alzheimer’s disease diagnostics: detection of amyloid beta biomarkers
Article first published online: 23 APR 2012
© 2012 The Authors. Journal of Neurochemistry © 2012 International Society for Neurochemistry
Journal of Neurochemistry
Volume 122, Issue 2, pages 374–381, July 2012
How to Cite
Prabhulkar, S., Piatyszek, R., Cirrito, J. R., Wu, Z.-Z. and Li, C.-Z. (2012), Microbiosensor for Alzheimer’s disease diagnostics: detection of amyloid beta biomarkers. Journal of Neurochemistry, 122: 374–381. doi: 10.1111/j.1471-4159.2012.07709.x
- Issue published online: 2 JUL 2012
- Article first published online: 23 APR 2012
- Accepted manuscript online: 28 FEB 2012 01:11PM EST
- Received December 12, 2011; revised manuscript received January 30, 2012; accepted February 6, 2012.
- Alzheimer’s disease;
- amyloid beta;
J. Neurochem. (2012) 122, 374–381.
Alzheimer’s disease (AD) affects about 35.6 million people worldwide, and if current trends continue with no medical advancement, one in 85 people will be affected by 2050. Thus, there is an urgent need to develop a cost-effective, easy to use, sensor platform to diagnose and study AD. The measurement of peptide amyloid beta (Aβ) found in CSF has been assessed as an avenue to diagnose and study the disease. The quantification of the ratio of Aβ1–40/42 (or Aβ ratio) has been established as a reliable test to diagnose AD through human clinical trials. Therefore, we have developed a multiplexed, implantable immunosensor to detect amyloid beta (Aβ) isoforms using triple barrel carbon fiber microelectrodes as the sensor platform. Antibodies act as the biorecognition element of the sensor and selectively capture and bind Aβ1–40 and Aβ1–42 to the electrode surface. Electrochemistry was used to measure the intrinsic oxidation signal of Aβ at 0.65 V (vs. Ag/AgCl), originating from a single tyrosine residue found at position 10 in its amino acid sequence. Using the proposed immunosensor Aβ1–40 and Aβ1–42 could be specifically detected in CSF from mice within a detection range of 20–50 nM and 20–140 nM respectively. The immunosensor enables real-time, highly sensitive detection of Aβ and opens up the possibilities for diagnostic ex vivo applications and research-based in vivo studies.