Year: 2003
Type: dissertation
Abstract: Dissociated nerve cells in culture are an accessible experimental tool for analyzing the behavior of networks of nerve cells that underlie the operation of the brain.Previous work has demonstrated the ability to constrain and influence the behavior of growing neurons by arrangement of substrate-bound chemical patterns, but these techniques have various limitations.In particular, techniques that employ photolithography to form patterns, such as microcontact printing, photolithography, and microfabricated microfluidics, require the use of an un-alterable previously existing mask.In this work a high-resolution ink-jet printer was designed and built to programmably pattern surface materials for neuroscience, overcoming some of the weaknesses of lithographic-based fabrication technology.An ink-jet printer operates by individually ejecting microscopic liquid droplets, 10 to 100 micrometers across, under computer control, as the print head is robotically moved in two dimensions a small distance above a substrate, leaving a pattern of deposited material.A range of biomaterials, including MatriGel, collagen, polylysine, RADA-motif self-assembling peptides, and laminin were printed.Ink-jet printed patterns of collagen/polylysine ink onto inhibitory polyethylene glycol backgrounds constrained the growth of primary rat hippocampal neurons for periods longer than three weeks.Patterns included dots and lines with feature sizes as small as 65 micrometers, connected islands, adjacent parallel lines with gaps as small as 5 micrometers maintained over millimeter distances, text, and out-of-plane wax structure such as walls and tunnels.Neurons on these patterns showed healthy resting potentials, spontaneous activity, and comparable concentrations of inhibitory cells and synaptic puncta to non-patterned control cells.The printer was also able to fabricate surfacebound gradients of laminin, which could enable directional axon specification.The printer thus provided a rapid means for arranging chemical constraints for neuron growth and proved to be a versatile tool able to aid in unique experiments.This work represents the first known application of ink-jet printing to patterning neurons in culture.
Author: Sawyer B. Fuller
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
Funder: National Science Foundation
OpenAlex ID: W2287569277