Jump to main content
Jump to site search

Issue 12, 2012
Previous Article Next Article

Ultra-rapid laser protein micropatterning: screening for directed polarization of single neurons

Author affiliations

Abstract

Protein micropatterning is a powerful tool for studying the effects of extracellular signals on cell development and regeneration. Laser micropatterning of proteins is the most flexible method for patterning many different geometries, protein densities, and concentration gradients. Despite these advantages, laser micropatterning remains prohibitively slow for most applications. Here, we take advantage of the rapid multi-photon induced photobleaching of fluorophores to generate sub-micron resolution patterns of full-length proteins on polymer monolayers, with sub-microsecond exposure times, i.e. one to five orders of magnitude faster than all previous laser micropatterning methods. We screened a range of different PEG monolayer coupling chemistries, chain-lengths and functional caps, and found that long-chain acrylated PEG monolayers are effective at resisting non-specific protein adhesion, while permitting efficient cross-linking of biotin-4-fluorescein to the PEG monolayers upon exposure to femtosecond laser pulses. We find evidence that the dominant photopatterning chemistry switches from a two-photon process to three- and four-photon absorption processes as the laser intensity increases, generating increasingly volatile excited triplet-state fluorophores, leading to faster patterning. Using this technology, we were able to generate over a hundred thousand protein patterns with varying geometries and protein densities to direct the polarization of hippocampal neurons with single-cell precision. We found that certain arrays of patterned triangles as small as neurite growth cones can direct polarization by impeding the elongation of reverse-projecting neurites, while permitting elongation of forward-projecting neurites. The ability to rapidly generate and screen such protein micropatterns can enable discovery of conditions necessary to create in vitro neural networks with single-neuron precision for basic discovery, drug screening, as well as for tissue scaffolding in therapeutics.

Graphical abstract: Ultra-rapid laser protein micropatterning: screening for directed polarization of single neurons

  • This article is part of the themed collection: Focus on USA
Back to tab navigation

Supplementary files

Article information


Submitted
14 Nov 2011
Accepted
09 May 2012
First published
17 May 2012

Lab Chip, 2012,12, 2265-2276
Article type
Paper

Ultra-rapid laser protein micropatterning: screening for directed polarization of single neurons

M. A. Scott, Z. D. Wissner-Gross and M. F. Yanik, Lab Chip, 2012, 12, 2265
DOI: 10.1039/C2LC21105J

Social activity

Search articles by author

Spotlight

Advertisements