|
The emerging field of nanotechnology offers the development of new materials and methods for crucial neuroscience
applications namely (a) promoting survival and growth of the neurons, and (b) monitoring physiological signals
generated in the nervous system such as excitation, synaptic transmission, release of neurotransmitter molecules and
cell-to-cell communication. Such bio-devices will have several novel applications in basic science, laboratory
analysis and therapeutic treatments. Our goals in this field of research include (a) development of new biocompatible
substrates to guide and promote neuronal growth along specific pathways; (b) designing a neuron-friendly,
bio-molecule delivery system for neuroprotection; (c) monitoring of electrical activity from neuron and also from
neuronal networks; (d) determining the diffusion and intracellular localization of nanomaterial interacting with
neurons at high resolution; and (e) detection of release of neurotransmitter molecules by means of newly designed
nanosensors. Here we describe the fabrication and use of magnetic nanotubes and nanowire electrode arrays in studies
using a cell culture model of neuronally differentiating rat pheochromocytoma (PC 12) cells. The magnetic nanotubes
were fabricated by a template method yielding hematite (α-Fe2O3) nanotubes. These nanotubes were coupled with
nerve growth factor (NGF). Vertically aligned nanowires were fabricated on glass substrates using the
lithography-assisted template bonding (LATB) method. Rat pheochromocytoma (PC12) cells were cultured on these
nanotubes and polylysine coated nanowire electrodes. Our results showed that magnetic nanotube bound NGF was
available to PC12 cells as they showed significant differentiation into neurons. PC12 cells growing on nanowires in
the presence of NGF differentiated into neurons capable of synthesis and release of dopamine upon stimulation. The
neurons grew healthy neurites appearing to form synapses with other neurons in the dish. These results show that the
magnetic nanotubes were capable of delivering neurotrophic molecules and the nanowire electrodes are
neuron-friendly, promote cell to cell communication and can be used as bio-sensors in the nervous system.
|
