Microelectrode Biosensors for in vivo Analysis of Brain Interstitial Fluid

Chemical analyses of brain interstitial fluid can reveal important information about local brain metabolism and neurochemistry, and can enhance our understanding of how neuronal networks respond to physiological or pathological stimuli. Among brain monitoring methods currently available, microelectrode biosensors provide real-time analyses with high temporal resolution and minimal perturbation to living tissue by using oxidase enzymes for biological recognition. Two types of microelectrodes are used: cylindrically shaped wire electrodes provide the smallest implantable devices to date, and microfabricated multi-electrode needles can monitor several molecules simultaneously. They have already contributed significantly to our understanding of brain energy metabolism with glucose and lactate detection, and to neurotransmitter systems with glutamate, D-serine, acetylcholine, and purine detection. They have the potential to undergo further technological developments in future studies.