Neuroprotection at the nanolevel--Part II: Nanodevices for neuromodulation--deep brain stimulation and spinal cord injury

Abstract

Nanotechniques presented in this article's companion report are being multiplexed into nanodevices that promise to greatly advance our understanding and treatment of many nervous system disorders. Current neuromodulation techniques for deep brain stimulation have major drawbacks, such as large size (in comparison with ideal of small neuron group stimulation), lack of feedback monitoring of brain electrical activity, and high electrical current needs. Carbon nanotube nanoelectrode arrays address these drawbacks and offer the possibility of monitoring neurotransmitter levels at the synapse/neuronal level in real time. Such arrays can monitor and modulate electrochemical events occurring among neural networks, which should add greatly to our understanding of neuronal communication. A multiplex nanodevice for studying (and enhancing) axonal regeneration after spinal cord injury is also being developed. The nanotechniques described in the companion piece are combined in a micron-sized neural growth tube lined with nanodevices through which the regenerating axon extends--allowing continuous monitoring and modulation of the axon's electrochemical environment plus directional guidance with a biodegradable nanoscaffold. Multifunction nanodevices provide opportunities for neuronal (and subneuronal) monitoring and modulation that will enhance neuroprotection and neurorepair far beyond the micro- and macrolevel techniques used heretofore.