Bioinspired Patterning with Extreme Wettability Contrast on TiO₂ Nanotube Array Surface: A Versatile Platform for Biomedical Applications

Abstract

Binary wettability patterned surfaces with extremely high wetting contrasts can be found in nature on living creatures. They offer a versatile platform for microfluidic management. In this work, a facile approach to fabricating erasable and rewritable surface patterns with extreme wettability contrasts (superhydrophilic/superhydrophobic) on a TiO2 nanotube array (TNA) surface through self-assembly and photocatalytic lithography is reported. The multifunctional micropatterned superhydrophobic TNA surface can act as a 2D scaffold for site-selective cell immobilization and reversible protein absorption. Most importantly, such a high-contrast wettability template can be used to construct various well-defined 3D functional patterns, such as calcium phosphate, silver nanoparticles, drugs, and biomolecules in a highly selective manner. The 3D functional patterns would be a versatile platform in a wide range of applications, especially for biomedical devices (e.g., high-throughput molecular sensing, targeted antibacterials, and drug delivery). In a proof-of-concept study, the surface-enhanced Raman scattering and antibacterial performance of the fabricated 3D AgNP@TNA pattern, and the targeted drug delivery for site-specific and high-sensitivity cancer cell assays was investigated.

Recent Advances in TiO2‐Based Nanostructured Surfaces with Controllable Wettability and Adhesion

“…The results indicate that the combination of special wettability, inherent photocatalysis of TiO 2 , and Ag particles decoration have largely enhanced the anti-bacterial activity. [ 108 ] …”

TiO₂ nanotube platforms for smart drug delivery: a review

“…Other biocompatibility researches further demonstrated a higher alkaline phosphatase activity based on better cell growth on TNTs in vivo conditions. [64][65][66] Oh et al …”

Smart Drug Delivery Strategies Based on Porous Nanostructure Materials

“…TiO 2 nanotubes have been studied predominantly in the field of photocatalysis [74][75][76], solar cells [77], and biomedical engineering [78][79][80], because of their excellent photocatalytic activity and biocompatibility. In addition, the high surface area and unique shape of TiO 2 nanotubes make them a promising option for application in drug delivery systems.…”