Centuries of research and billions of dollars of investment have effectively brought humanity under the dominance of ‘1’ and ‘0’. Concurrently, millennia of evolution have seen a different language develop in the natural world: one of singular value and purpose. While the language of digital communication — radio, television, internet, wireless — has defined ‘Hello’ as the cumbersome ‘01001000 01000101 01001100 01001100 01001111’, a the bio-chemical world will represent it by a single molecule.
An international group of scientists, including Shannon Olsson from the Bengaluru-based National Centre for Biological Sciences (NCBS), have sought to define these ‘singular values’ based on ‘Nature’s language’.
“A single molecule or small mixtures of molecules can inform a bacteria where to find sugar, a plant when it is being attacked, or even an elephant when it is mating time…immense amount of information is given through a few values,” says Shannon Olsson from NCBS, an author of the study published Bioinspiration and Biomimetics recently. The team developed prototypes using the ‘pheromones’ of a moth. A female moth releases minute packets of pheromones over several meters to attract a male for mating. “We chose this system because it is a preeminent example of chemical communication,” says Prof. Olsson.
Electronic components then mimicked the four stages of bio-chemical communication: production, transmission, detection and processing of the chemical signal. A tiny micro-reactor produces a cocktail of chemicals (which have the same characteristics of a pheromone) and an emitter (a silicon-glass evaporator) mimics the glands of a female moth to let out the chemicals in a regulated manner.
The effectiveness of the ‘chemoemitter’ (chemicals, emitter) was demonstrated in the changes in behaviour of male moths, which behaved as they would on ‘scenting’ “virgin females”. A chemoreceiver was developed to decode the chemical signals. The microsensor uses an insect olfactory receptor found in a fruit fly (Drosophila). A pheromone molecule triggers a signal, which is deciphered using software.
The potential is limitless. “There is vast potential: from environmental monitoring to intracellular therapy to nanoscale communication. The system can monitor drug release inside the body or tell you when mangoes smell ripe for picking in an orchard,” says Ms. Olsson.
