Glutamate sensing with enzyme-modified floating-gate field effect transistors
| Autor: | Geert Callewaert, Shlomo Yitzchaik, Dries Braeken, Rik Huys, J. Shappir, Carmen Bartic, Gustaaf Borghs, Alexandru Andrei, Danielle Rand, Micha E. Spira |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
Transistors
Electronic Biomedical Engineering Biophysics Glutamic Acid Nanotechnology 02 engineering and technology Biosensing Techniques Neurotransmission 01 natural sciences Sensitivity and Specificity Reuptake chemistry.chemical_compound Electrochemistry Microelectronics Neurotransmitter Detection limit business.industry 010401 analytical chemistry Glutamate receptor Reproducibility of Results General Medicine Quartz crystal microbalance Equipment Design Micro-Electrical-Mechanical Systems 021001 nanoscience & nanotechnology 0104 chemical sciences Equipment Failure Analysis chemistry 0210 nano-technology business Oxidoreductases Biosensor Biotechnology |
| Zdroj: | Biosensors and Bioelectronics |
| ISSN: | 0956-5663 |
| DOI: | 10.1016/j.bios.2008.12.012 |
| Popis: | Neurotransmitter release is the key factor of chemical messaging in the brain. Fast, sensitive and in situ detection of single cell neurotransmitter release is essential for the investigation of synaptic transmission under physiological or pathophysiological conditions. Although various techniques have been developed for detecting neurotransmitter release both in vitro and in vivo, the sensing of such events still remains challenging. First of all, the amount of neurotransmitter released during synaptic transmission is unknown because of the limited number of molecules released and the fast diffusion and reuptake of these molecules after release. On the other hand, advances in microelectronic biosensor devices have made possible the fast detection of various analytes with high sensitivity and selectivity. Specifically, enzyme-modified field-effect (ENFET) devices are attractive for such applications due to their fast response, small dimensions and the possibility to integrate a large number of sensors on the same chip. In this paper, we present a floating-gate FET device coated with glutamate oxidase (GLOD) layer. The surface chemistry was optimized for maximal enzyme loading and long-term stability, and characterized by quartz crystal microbalance and colorimetric assays. Enzyme loading was largest on poly-l-lysin-based surfaces combined with glutaraldehyde. The surface chemistry showed excellent stability for at least one month in Tris buffers stored at 4 ◦C. A glutamate detection limit of 10−7 M has been obtained with the GLOD-coated FET and our sensor proved to be selective to glutamate only. We show that this biosensor is a promising tool for the in vitro detection of glutamate and can be extended to other neurotransmitters. © 2008 Elsevier B.V. All rights reserved. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect