Abstract
The external epithelial surfaces of plants and animals are frequently carpeted with small micro- and nanostructures, which broadens their adaptive capabilities in challenging physical habitats. Hairs and other shaped protuberances manage with excessive water, light contaminants, predators or parasites in innovative ways. We are interested in transferring these intricate architectures onto biomedical devices and daily-life surfaces. Such a project requires a very rapid and accurate small-scale fabrication process not involving lithography. In this study, we describe a simple benchtop biotemplating method using shed gecko lizard skin that generates duplicates that closely replicate the small nanotipped hairs (spinules) that cover the original skin. Synthetic replication of the spinule arrays in popular biomaterials closely matched the natural spinules in length. More significantly, the shape, curvature and nanotips of the synthetic arrays are virtually identical to the natural ones. Despite some small differences, the synthetic gecko skin surface resisted wetting and bacterial contamination at the same level as natural shed skin templates. Such synthetic gecko skin surfaces are excellent platforms to test for bacterial control in clinical settings. We envision testing the biocidal properties of the well-matched templates for fungal spores and viral resistance in biomedicine as well as co/multi-cultures.
Highlights
Engineered surfaces bearing tiny structures at the nanoscale are typically made with techniques translated from the semiconductor and electronics industries, such as electron and ion-based lithography[19], hard lithography[20], photo and soft lithography[16], which can duplicate very small features to below 50 nm in dimensions
We have focused on analyzing spinule morphology and have not considered other elements that could contribute to the decontamination functions of the skin
From Scanning Electron Microscopy (SEM) images of truncated spinules, there was no evidence of an internal structure that would indicate a mechanical or sensory function
Summary
Engineered surfaces bearing tiny structures at the nanoscale are typically made with techniques translated from the semiconductor and electronics industries, such as electron and ion-based lithography[19], hard lithography[20], photo and soft lithography[16], which can duplicate very small features to below 50 nm in dimensions. One taxonomic group of lizards, the gecko, has caught our attention because of the superhydrophobicity and unique design of their hair structures and associated topography, which have profound antimicrobial action[2]. These hair-like protuberances develop across the entire body, and interestingly, when the gecko animal sheds its skin, the structures remain perfectly intact[27,28]. We adapted a simple biotemplating methodology based on the casting and molding strategy to generate excellent copies of spinules onto materials measuring up to 10 × 10 cm (for some species). While printing and imprinting techniques, plotted by 3D digital imaging possess the capability to replicate surface features with unsurpassed levels of accuracy and precision, in this study we favoured the benchtop procedure to generate structures that can be rapidly employed in laboratory testing and evaluation studies
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have