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A Method of Targeted Cell Isolation via Glass Surface Functionalization
Published on: September 20, 2016
Surface Free Energy Determination of APEX Photosensitive Glass
William R Gaillard1, Emanuel Waddell2, John D Williams3
1Department of Electrical and Computer Engineering, University of Alabama in Huntsville, Huntsville, AL 35899, USA. wrg0001@uah.edu.
Abstract:
Surface free energy (SFE) plays an important role in microfluidic device operation. Photosensitive glasses such as APEX offer numerous advantages over traditional glasses for microfluidics, yet the SFE for APEX has not been previously reported. We calculate SFE with the Owens/Wendt geometric method by using contact angles measured with the Sessile drop technique. While the total SFE for APEX is found to be similar to traditional microstructurable glasses, the polar component is lower, which is likely attributable to composition. The SFE was modified at each stage of device fabrication, but the SFE of the stock and fully processed glass was found to be approximately the same at a value of 51 mJ·m-2. APEX exhibited inconsistent wetting behavior attributable to an inhomogeneous surface chemical composition. Means to produce more consistent wetting of photosensitive glass for microfluidic applications are discussed.
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