Project 2

Bio-Inspired Surfaces: Fabrication of shark skin using glancing angle deposition

(Prof. Kevin Walsh and Dr. Chuang Qu, ECE)

Natural micro/nano-structures often serve as remarkable sources of inspiration for engineering innovations. Examples include the nanostructures found on cicada wings [1], lotus leaves [2], and moth eyes. [3] In this research, the Walsh/Qu Research Team focuses on the microstructures found on shark skin known as dermal denticles (Fig. -left). These structures exhibit interesting hydrophobic, drag-reducing [4], and anti-fouling properties that hold great potential across domains, such as healthcare, medical devices, and industrial settings. While some methods exist for replicating shark skin, they suffer from being unreliable, inefficient, costly, and not scalable. [5-7] To address these limitations, our team leverages Glancing Angle Deposition (GLAD) [8-9], a physical vapor deposition that involves high incident angles to the substrate. By integrating GLAD with well-designed 2D seed structures, we have created complex 3D microstructures resembling the ridges found in dermal denticles (Fig. -right). In this summer experience, the REU student will characterize existing synthetic samples to evaluate their properties, such as morphology using SEM imaging and hydrophobicity using water contact angle. The information gathered will then be used to develop the next generation of our synthetic shark skin mimicries. Students interested in BE, ME, ChE, ECE, Chem, Physics, or Bio will be excellent candidates.

References:

1. Centner, C.S., et al., Acoustofluidic-mediated molecular delivery to human T cells with a three-dimensional-printed flow chamber. J Acoust Soc Am, 2021. 150(6): p. 4534.

2. Centner, C.S., et al., Comparison of Acoustofluidic and Static Systems for Ultrasound-Mediated Molecular Delivery to T Lymphocytes. Ultrasound Med Biol, 2023. 49(1): p. 90-105. 

3. Centner, C.S., et al., Ultrasound-induced molecular delivery to erythrocytes using a microfluidic system. Biomicrofluidics, 2020. 14(2): p. 024114.

4. Centner, C.S., et al., Assembly and Operation of an Acoustofluidic Device for Enhanced Delivery of Molecular Compounds to Cells. J Vis Exp, 2021(167).

5. Qu, C. et al. Bio-inspired antimicrobial surfaces fabricated by glancing angle deposition. Sci. Rep. 13, 207 (2023).

6. Jiang, R. et al. Lotus-leaf-inspired hierarchical structured surface with non-fouling and mechanical bactericidal performances. Chem. Eng. J. 398, 125609 (2020).

7. Ji, S., Park, J. & Lim, H. Improved antireflection properties of moth eye mimicking nanopillars on transparent glass: Flat antireflection and color tuning. Nanoscale 4, 4603–4610 (2012).

8. Wen, L., Weaver, J. C. & Lauder, G. V. Biomimetic shark skin: Design, fabrication and hydrodynamic function. J. Exp. Biol. 217, 1656–1666 (2014).

9. Wen, J., Prawel, D. & Li, Y. V. A study on the mechanical and antimicrobial properties of biomimetic shark skin fabrics with different denticle size via 3D printing technology. Phys. Scr. 98, (2023).