Enzyme-Immobilized CNT Network Probe for In Vivo Neurotransmitter Detection
Glutamate is the principal excitatory neurotransmitter in the brain, and its excessive release plays a key role in neuronal death associated with a wide range of neural disorders. Real-time monitoring of extracellular glutamate levels would be very helpful in understanding the excitotoxic process of neurotransmitters on brain injury. Toward the detection of l-glutamate, we describe in this chapter the preparation of carbon nanotube (CNT) network probes with immobilized l-glutamate oxidase (GLOD) by using a non-covalent functionalized method. Such GOLD-CNT network probes are evaluated with real-time electronic responses corresponding to standard glutamate solutions in vitro and a 11-vessel occlusion (11 VO) rat model in vivo. The ultrahigh sensitivity, selectivity, and fast response time of GLOD-CNT network probes are greatly promising for the real-time electronic detection of extracellular glutamate levels in brain.
Key wordsGlutamate CNT network probe in vivo real-time detection GLOD immobilization
This study was supported by the research fund from the Ministry of Commerce, Industry, and Energy (MOCIE Grant #10017190-2007-31), and Bio R&D program through MEST (2010-0019912). We greatly appreciate Mr. B.Y. Lee, Mr. D.H. Son, and Prof. S. Hong at Seoul National University who provided the CNT probes.
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