Hebrew University of Jerusalem researchers have developed a safe new method of preventing mosquito bites using a skin coating from naturally occurring cellulose nanocrystals (CNCs).

A mosquito. Photo courtesy of Wikimedia Commons.

According to a study published in PNAS NEXUS, applying the thin CNC coating on human skin decreases the number of mosquitoes feeding by 80%. Cellulose CNCs are a renewable raw material produced from wood, cotton or other cellulose-rich sources and are used in cosmetics, composites, food packaging and medical devices.

“Combining CNCs with the mosquito repellent indole confirmed its excellent potential as safe and sustainable mosquito prevention,” said lead researcher Prof. Jonathan Bohbot, of Hebrew University’s Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, Food and Environment.

“CNC biocompatibility, ubiquity and the potential for cost-effective mass production could result in a new generation of mosquito personal protective measures,” he added.

Mosquitoes are the deadliest of all insects and animals, affecting millions and killing hundreds of thousands of people annually. Existing protection methods, however, are limited and include volatile compounds that actively repel mosquitoes such as N,N-Diethyl-meta-toluamide (DEET) and other oils such as geraniol and citronella.

CNC appears to act as a chemical camouflage to the many cues sought by the insects and was found to reduce the blood feeding in the deadly mosquito Aedes aegyptiIt was tested on a single human hand and on an artificial feeding system by assessing the eggs laid after feeding with and without CNC.

The combined effect of CNC with indole reduced egg laying post exposure to mammalian blood to close to zero, with 99.4% fewer eggs compared to the control.