Fiber Optic Biosensors for Glutamate

基于光纤技术的谷氨酸生物传感探针将得到发展。这些探针由固定在光纤蒸馏端部的谷氨酸脱氢酶组成。该酶催化谷氨酸与氧化的烟酰胺腺嘌呤二核苷酸反应生成2-氧戊二酸、氨和还原的烟酰胺腺嘌呤二核苷酸（NADH）。NADH的产生是通过荧光或生物发光过程监测的。在这两种情况下，都会产生与谷氨酸样品浓度有关的稳态信号。如果成功，提议的谷氨酸生物传感器将适用于体内研究，以确定谷氨酸的神经特性。这些传感器将允许在完整的神经组织中局部、组织内测量谷氨酸（可能还有天冬氨酸）。这种局部测量可以潜在地将这些假定的神经递质的突触与非突触池分开。此外，一种无试剂的谷氨酸探针也将被研究作为一种连续的，体内谷氨酸测量的手段。

Glutamate biosensing probes based on fiber optic technology will be developed. These probes consist of the enzyme glutamate dehydrogenase immobilized at the distill tip of an optical fiber. This enzyme catalyzes the reaction between glutamate and oxidized nicotinamide adenine dinucleotide to form 2-oxoglutarate, ammonia and reduced nicotinamide adenine dinucleotide (NADH). The generation of NADH is monitored by either a fluorescence or bioluminescence process. In both cases, a steady-state signal is produced which can be related to the sample concentration of glutamate. If successful, the proposed glutamate biosensors will be suitable for in vivo studies to determine the neurological properties of glutamate. These sensors will allow localized, intratissue measurements of glutamate (and possibly aspartate) in intact neuoral tissue. Such localized measurements can potentially separate synaptic from non-synaptic pools of these putative neurotransmitters. In addition, a reagent-less glutamate probe will also be investigate as a means to make continuous, in vivo glutamate measurements.