Micropatterned structures for studying the mechanics of biological polymers.
Studying the mechanics of nanometer-scale biomolecules presents many challenges; these include maintaining light microscopy image quality and avoiding interference with the laser used for mechanical manipulation, that is, optical tweezers. Studying the pushing forces of a polymerizing filament requires barriers that meet these requirements and that can impede and restrain nanoscale structures subject to rapid thermal movements. We present a flexible technique that meets these criteria, allowing complex barrier geometries with undercut sidewall profiles to be produced on #1 cover glass for the purpose of obstructing and constraining polymerizing filaments, particularly microtubules. Using a two-layer lithographic process we are able to separate the construction of the primary features from the construction of a depth and shape-controlled undercut. The process can also be extended to create a large uniform gap between an SU-8 photoresist layer and the glass substrate. This technique can be easily scaled to produce large quantities of shelf-stable, reusable microstructures that are generally applicable to microscale studies of the interaction of cellular structures with defined microscale features.
Schek
Henry T
HT
Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA, tschek@umich.edu
Hunt
Alan J
AJ
D001696:Biomechanical Phenomena / Q000379:methods; D001704:Biopolymers / Q000032:analysis* / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000032:analysis* / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008846:Micromanipulation / Q000295:instrumentation* / Q000379:methods*; D008858:Microscopy, Phase-Contrast / Q000295:instrumentation / Q000379:methods; D008870:Microtubules / Q000737:chemistry* / Q000648:ultrastructure*; D008968:Molecular Conformation; D010781:Photography / Q000295:instrumentation / Q000379:methods; D013499:Surface Properties
D001704:Biopolymers; D020099:Coated Materials, Biocompatible