A ceramic-based microelectrode array (MEA) with enzyme coatings for the accurate measurement of acetylcholine (ACh) in brain tissues is presented. Novel design features allow for self-referencing recordings for improved limits of detection and highly selective measurements of ACh and choline (Ch), simultaneously. Design and fabrication features also result in minimal tissue damage during implantation and improved enzyme coatings due to isolated recording sites. In these studies we have used a recombinant human acetylcholinesterase enzyme coating, which has better reproducibility than other commercially available enzymes. The precisely patterned recording site dimensions, low limit of detection (0.2 μM) and fast response time (∼1 s) allow for second-by-second measurements of ACh and Ch in brain tissues. An electropolymerized meta-phenylenediamine (mPD) layer was used to exclude interfering substances from being recorded at the platinum recording sites. Our studies support that the mPD layer was stable for over 24 h under in vitro and in vivo recording conditions. In addition, our work supports that the current configuration of the MEAs produces a robust design, which is suited for measures of ACh and Ch in rat brain.
|Number of pages||8|
|Journal||Biosensors and Bioelectronics|
|State||Published - Apr 15 2008|
Bibliographical noteFunding Information:
The authors would like to acknowledge Andrew Allen of the University of Kentucky Center for Microelectrode Technology. Support Contributed By: USPHS grant MH58414, NSF DBI-0352848, DARPA N66001-02-C-8058, NSF ERC (BMES) and DA019502.
ASJC Scopus subject areas
- Biomedical Engineering