Project 5:

Biosensor for neurochemicals

We develop novel microelectrode sensor technology that can be applied directly to implantable neural electrode arrays. Real time monitoring of neurotransmitter levels can provide information on the dynamics and magnitude of the cellular reactions around the electrodes.  Monitoring neurotransmitters and modulators while recording electrical activity of neurons is highly desired for mapping neural circuits and understanding brain functions. Sensor design is tailored to be selective for the desired analyte. Using advanced material science and technology, we have developed sensors for catecholamine neurotransmitters such as dopamine and serotonin by using various nanocarbon and conducting polymers with higher sensitivity than the state of art[1-5]. We also employ enzyme biosensors to detect non-electroactive analytes such as glutamate and GABA from neural tissues6. Additionally, our lab has extensive experience using aptamer-based sensors for a wide variety of analytes, including cytokines and cocaine7-9.


1. Taylor, I. M. et al. Enhanced dopamine detection sensitivity by PEDOT/graphene oxide coating on in vivo carbon fiber electrodes. Biosens Bioelectron 89, 400-410, doi:10.1016/j.bios.2016.05.084 (2017).

2. Castagnola, E., Garg, R., Rastogi, S. K., Cohen-Karni, T. & Cui, X. T. 3D fuzzy graphene microelectrode array for dopamine sensing at sub-cellular spatial resolution. Biosens Bioelectron 191, 113440, doi:10.1016/j.bios.2021.113440 (2021).

3. Castagnola, E. et al. Flexible Glassy Carbon Multielectrode Array for In Vivo Multisite Detection of Tonic and Phasic Dopamine Concentrations. Biosensors (Basel) 12, doi:10.3390/bios12070540 (2022).

4. Nam, K. H. et al. Laser direct write of heteroatom-doped graphene on molecularly controlled polyimides for electrochemical biosensors with nanomolar sensitivity. Carbon N Y 188, 209-219, doi:10.1016/j.carbon.2021.10.010 (2022).

5. Taylor, I. M., Patel, N. A., Freedman, N. C., Castagnola, E. & Cui, X. T. Direct in Vivo Electrochemical Detection of Resting Dopamine Using Poly(3,4-ethylenedioxythiophene)/Carbon Nanotube Functionalized Microelectrodes. Anal Chem 91, 12917-12927, doi:10.1021/acs.analchem.9b02904 (2019).

6. Tan, C., Kushwah, N. & Cui, X. T. Electrically Controlled Neurochemical Delivery from Microelectrodes for Focal and Transient Modulation of Cellular Behavior. Biosensors (Basel) 11, doi:10.3390/bios11090348 (2021).

7. Taylor, I. M. et al. Aptamer-functionalized neural recording electrodes for the direct measurement of cocaine in vivo. J Mater Chem B 5, 2445-2458, doi:10.1039/C7TB00095B (2017).

8. Liao, W. & Cui, X. T. Reagentless aptamer based impedance biosensor for monitoring a neuro-inflammatory cytokine PDGF. Biosens. Bioelectron. 23, 218-224 (2007).

9. luo, X. L., Lee, I., Huang, J. Y., Yun, M. H. & Cui, X. Y. T. Ultrasensitive protein detection using an aptamer-functionalized single polyaniline nanowire. Chem Commun 47, 6368-6370, doi:10.1039/c1cc11353d (2011).