Abstract We synthesized novel TiO2/ZnO-phosphate (TP/ZP) and polymethyl hydrogen siloxane (PMHS)-based two-layer hydrophobic coatings with potential antimicrobial properties tuned for application on steel substrates. The mathematical method of topological data analysis was applied to surface roughness data. Wetting characterizations showed stable hydrophobic behavior of the two-layer coated samples. Through tribological characterization, we compared the friction behavior of uncoated steel samples and steel samples coated with different coating materials. The coefficient of friction of uncoated base materials (ranging from 0.221 to 0.269) and the two-layer hydrophobic coatings (ranging from 0.234 to 0.273) indicated that the coatings confer hydrophobic properties to the substrates without a notable change in the friction behavior. We observed the correlations between the wetting and friction behaviors and the average roughness of the coated samples. Analysis of the micrographs of the scratched surfaces revealed preliminary information about the durability and abrasion resistance of the coatings.
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BIOMIMICKING HYDROPHOBICITY USING MICROSCALE STRUCTURES FOR BIOMEDICAL APPLICATIONS
Hydrophobic surfaces provide special characteristics for biomedical applications ranging from tunable protein adsorption, cellular interactions, and hemocompatibility to antibacterial coatings. In this research, we biomimic the hair-like micro-whisker structures of magnolia leaf using a synthetic polymeric formulation. Optical and scanning electron microscopy images revealed the presence of micro-whiskers resulting in higher water contact angles. The top layer of the magnolia leaf had a contact angle of 50º as compared to the hydrophobic bottom layer at 98º. A synthetic polymeric formulation was coated on different materials to study its effect on hydrophobicity. The coating was replicated (n=3) on each of the materials used such as glass, polymer, fabric, wood, and stainless steel. A surface tensiometer was used to measure the transition from hydrophilic to hydrophobic interactions between water and the substrate materials. Contact angle measurements revealed an increase in hydrophobicity for all the materials from their original uncoated surface. Glass displayed the highest increase in contact angle from 37º to 90º. Phase analysis of the coated region was performed to characterize the surface exposure of glass substrate to the synthetic polymeric formulation. An increase in the coated region showed a significant increase in contact angle from 50º to 95º. This research lays the foundation to develop and understand hydrophobic coatings for several biomedical applications including non-fouling implant surfaces, lab-on-chip devices, and other diagnostic tools.
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- Award ID(s):
- 2100710
- PAR ID:
- 10437462
- Date Published:
- Journal Name:
- Biomedical Sciences Instrumentation
- Volume:
- 58
- Issue:
- 3
- ISSN:
- 1938-1158
- Page Range / eLocation ID:
- 177 to 185
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.34107/LWWJ5713177
