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Control of Cell Adhesion using Hydrogel Patterning Techniques for Applications in Traction Force Microscopy
Published on: January 29, 2022
The deformation and adhesion of randomly rough and patterned surfaces
Marcel Benz1, Kenneth J Rosenberg, Edward J Kramer
1Department of Chemical Engineering, and Materials Research Laboratory, University of California, Santa Barbara, California 93106, USA.
The Journal of Physical Chemistry. B
|June 28, 2006
Summary
Surface roughness significantly impacts polymer contact mechanics. Random roughness causes exponential repulsion, while patterned surfaces show reduced adhesion with increased roughness, both exhibiting Hertzian deformation.
Area of Science:
- Materials Science
- Surface Science
- Polymer Physics
Background:
- Contact mechanics governs surface interactions, crucial for material performance.
- Surface roughness, quantified by root-mean-square (RMS) values, influences deformation and adhesion.
- Understanding these effects is vital for designing reliable polymeric materials and interfaces.
Purpose of the Study:
- To investigate the influence of varying surface roughness on the contact mechanics of polymeric materials.
- To differentiate the effects of random versus patterned surface roughness on deformation and adhesion.
- To correlate experimental findings with theoretical models and simulations.
Main Methods:
- Utilized a surface forces apparatus (SFA) and atomic force microscopy (AFM) to probe surface interactions.
- Studied polymeric surfaces with RMS roughness ranging from 0.3 to 220 nm.
- Employed finite element method (FEM) analysis using AFM topographical data for correlation.
Main Results:
- Randomly rough elastomeric surfaces exhibited nearly reversible, exponentially repulsive force-distance curves.
- Adhesion on separation decreased slightly with increasing RMS roughness for random surfaces.
- Patterned surfaces showed no exponential repulsion but dramatically reduced adhesion with increasing RMS roughness.
- Both surface types displayed Hertzian deformation at the macroscopic level.
Conclusions:
- Asperity height variability and random roughness are essential for observing exponential repulsive behavior.
- Contact area reduction with increasing RMS roughness significantly impacts adhesion in patterned surfaces.
- The preload force magnitude is a critical factor in determining measured adhesion.
- Hertzian mechanics adequately describes the large-scale deformation of both random and patterned rough surfaces.
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