Silicon-wafer based electroenzymatic glutamate biosensors for the near-real time monitoring of glutamate in freely-behaving rats

Glutamate is a ubiquitous excitatory neurotransmitter. We are interested in the role the glutamate system plays in both normal and aberrant motivated behavior, particularly with regards to its role in learning about both natural and drug rewards. Using Micro-Electro-Mechanical-System technologies we have developed silicon wafer-based platinum microelectrode arrays modified with glutamate oxidase (GluOx) for the near-real time sensitive and selective electroenzymatic detection of glutamate in the rodent brain. Using these biosensors we have recently shown transient glutamate concentration changes in the basolateral amygdala that are time-locked to motivated actions. Specifically, we observed glutamate transients surrounding reward-seeking actions. Moreover, the occurrence of these transients was significantly correlated with the performance of such actions.