Researchers at the University of Minho in Portugal have modified cotton fabric to emit a lemon smell upon contact with sweat. A story in sportstextiles.com reports that Carla Silva, Artur Cavaco-Paulo and colleagues wanted to develop two strategies for releasing citronellol, a lemongrass-derived scent used in some insect repellents.
The first approach involved an odorant-binding protein (OBP) found in pigs’ noses that binds to β-citronellol and other scent molecules. The researchers attached a protein domain, called a carbohydrate-binding module (CBM) that binds to cotton.
In their second strategy, the researchers packaged the fragrance in liposomes that displayed CBMs, which anchored the lipid carriers and their cargo to the fabric. The team exposed the modified cotton fabrics to an acidic sweat solution, and the low pH of the simulated perspiration caused the OBP and liposomes to release β-citronellol.
Comparing the two strategies revealed that the OBP released a quick burst of scent, while the liposomes showed a slower, controlled release. The liposomes could also hold more fragrance than the other approach. The two strategies could prove useful for different clothing applications, the researchers said.
The findings have been published in the ACS Applied Materials & Interfaces journal.