The RepelWrap is a transparent and flexible plastic film that significantly repels liquid and microbial contaminations (viruses and bacteria) from surfaces, keeping them clean even under the most contaminating conditions. The RepelWrap is an omniphobic surface technology (a surface repelling a broad range of contaminants), which uses engineered hierarchical materials to transform commercially-available plastic wraps into repellent films.
The RepelWrap uses a novel nature-inspired concept to build pathogen repellency onto plastic surfaces. This concept uses structural hierarchy, wrinkles in the micron lengthscale decorated with particles in the nanometer lengthscale that are functionalized with molecular layers, to repel contaminants by reducing surface energy and intermolecular forces. This programmable structural hierarchy is implemented on plastic surfaces using facile manufacturing processes (solution-processing) used by plastic manufacturers, demonstrating tremendous potential for large volume manufacturing. The RepelWrap can be manufactured onto biodegradable and green plastic materials to alleviate the increased concerns centered around materials sustainability and recyclability.
The RepelWrap has demonstrated remarkable properties in repelling a wide range of liquids including water, hexadecane, and blood with contact angles and sliding angles of 154°, 124°, 144°, <5°, respectively, indicating that liquid contaminants roll-off of these surfaces instead of sticking on them. The RepelWrap was tested with Pseudomonas spp. and methicillin resistant Staphylococcus aureus (both high priority pathogens by the World Health Organization), as well as the human simplex virus (HSV). The RepelWrap significantly reduced pathogen transfer and completely suppressed biofilm formation.
In the search to finding a solution for reducing the spread of COVID-19, we evaluated the RepelWrap by exposing it to viral contamination (using HSV having a similar size and morphology to SARS-CoV-2), demonstrating a remarkable more than 4 log 10 reduction in viral transfer, a number superior to that obtained with most disinfectants.
There is currently no technology of this type – a versatile flexible plastic wrap that works instantly on repelling a wide range of contaminants – available on the market. The existing antimicrobial surface technologies often use active antimicrobial agents that are either not universal, increase microbial resistance, have long-term health concerns, or require long pathogen deactivation times (minutes to hours). The RepelWrap with its instant and wide-range repellency and its ability to repel, rather than kill or deactivate pathogens, presents a unique and effective alternative to these technologies.
This technology was reported for the first time in 2019 through our patent filing and publication in a prestigious journal, ACS Nano (ACS nano 14 (1), 454-465). As a result of its novelty and potential impact in halting the spread of infections, this work has been widely covered in the main stream, scientific, and industry news through outlets such as CBC Radio, BBC Radio, CNN Health, Times of India, and Materials Today, to name a few.