Micropatterned Structures for Studying the Mechanics of Biological Polymers

• Published in: Biomedical microdevices Vol. 7; no. 1; pp. 41 - 46
• Main Authors: Schek, Henry T., Hunt, Alan J.
• Format: Journal Article
• Language: English
• Published: United States Springer Nature B.V 01.03.2005
• Subjects: Biomechanical Phenomena - methods; Biopolymers - analysis; Biopolymers - chemistry; Coated Materials, Biocompatible - analysis; Coated Materials, Biocompatible - chemistry; Equipment Design; Equipment Failure Analysis; Micromanipulation - instrumentation; Micromanipulation - methods; Microscopy, Phase-Contrast - instrumentation; Microscopy, Phase-Contrast - methods; Microtubules - chemistry; Microtubules - ultrastructure; Molecular Conformation; Photography - instrumentation; Photography - methods; Surface Properties
• ISSN: 1387-2176; 1572-8781
• DOI: 10.1007/s10544-005-6170-z

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.