The silk moth's antenna has inspired researchers from the University of Michigan to develop a better nanotechnology tool that could help understand a class of neurodegenerative diseases, including Alzheimer's.
Nanopores-essentially holes drilled in a silicon chip-are miniscule measurement devices that enable the study of single molecules or proteins.
Even today's best nanopores clog easily, so the technology has not been widely adopted in the lab.
"What this gives us is an improved tool to characterize biomolecules," said Michael Mayer, associate professor in U-M.
"It allows us to gain understanding about their size, charge, shape, concentration and the speed at which they assemble. This could help us possibly diagnose and understand what is going wrong in a category of neurodegenerative disease that includes Parkinson's, Huntington's and Alzheimer's," he added.
The researchers engineered an oily coating that traps and smoothly transports molecules of interest through nanopores. The coating also allowed them to adjust the size of the pore with close-to-atomic precision.
Mayer's 'fluid lipid bilayer' resembles a coating on the male silk moth's antenna that helps it smell nearby female moths.
The coating catches pheromone molecules in the air and carries them through nanotunnels in the exoskeleton to nerve cells that send a message to the bug's brain.
"These pheromones are lipophilic. They like to bind to lipids, or fat-like materials. So they get trapped and concentrated on the surface of this lipid layer in the silk moth. The layer greases the movement of the pheromones to the place where they need to be. Our new coating serves the same purpose," said Mayer.
To use nanopores in experiments, the researchers placed the pore-pricked chip between two chambers of saltwater. They dropped the molecules of interest into one of the chambers and sent an electric current through the pore.
As each molecule or protein passed through the pore, it changed the pore's electrical resistance. The amount of change observed provided valuable information about the molecule's size, electrical charge and shape.
Due to their small footprint and low power requirements, nanopores could also be used to detect biological warfare agents.
The study is published online in Nature Nanotechnology.