Superhydrophobic materials for biomedical applications

Abstract

Superhydrophobic surfaces are actively studied across a wide range of applications and industries, and are now finding increased use in the biomedical arena as substrates to control protein adsorption, cellular interaction, and bacterial growth, as well as platforms for drug delivery devices and for diagnostic tools. The commonality in the design of these materials is to create a stable or metastable air state at the material surface, which lends itself to a number of unique properties. These activities are catalyzing the development of new materials, applications, and fabrication techniques, as well as collaborations across material science, chemistry, engineering, and medicine given the interdisciplinary nature of this work. The review begins with a discussion of superhydrophobicity, and then explores biomedical applications that are utilizing superhydrophobicity in depth including material selection characteristics, in vitro performance, and in vivo performance. General trends are offered for each application in addition to discussion of conflicting data in the literature, and the review concludes with the authors’ future perspectives on the utility of superhydrophobic surfaces for biomedical applications.

Targeting microbial biofilms: current and prospective therapeutic strategies

“…Surface modifications are mostly focused on nonspecific protein repulsion and the inhibition of bacterial colonization. This can be challenging due to the structural and physio-chemical diversity of the numerous proteins in biological fluids surrounding a surface in a biomedical setting 115 . Hydrophilic polymer brushes or tethered polymers such as poly(ethylene glycol) (PEG) are widely used in the prevention of medical device fouling 116 .…”

Surface tension sensor meshes for rapid alcohol quantification

“…11 The partially wetted state accounts for the remarkable properties of superhydrophobic materials, which have been the subject of much research recently. 12–21 The transition between these two wetting states occurs at a specific surface tension and triggers a large change in apparent contact angle, and is the basis for the mechanism of our sensors. The alcohol sensors (Figure 1A) are composed of a) an upper ‘responsive’ layer that allows wetting of liquids only below a specific surface tension, and b) a hydrophilic lower ‘indicator’ layer that wets completely and provides a color change from the dissolution of the incorporated dye, bromocresol purple.…”

Mechanoresponsive materials for drug delivery: Harnessing forces for controlled release

“…Another strategy for constructing mechanoresponsive drug delivery systems relies on the triggered wetting of normally non-wetting or slowly-wetting drug-loaded materials, and is currently used for a variety of biomedical applications [134]. In this manner, water solubilizes the drug, causing subsequent release via diffusion into the surrounding aqueous environment.…”