Electrochemical DNA biosensors are a growing field and a new study published in PLoS Biology shows that the next generation in odor detection technology could involve artifical noses based on DNA.

The study demonstrates a previously unreported property of deoxyribonucleic acid; single-stranded DNA molecules tagged with a fluorescent reporter and dried onto solid surfaces can respond to vapor phase odor pulses in a sequence-selective manner.

In the context of detecting chemicals in either the aqueous or vapor phase, two general biological approaches have emerged. The first relies on individual, highly specific single receptors (sensors), each tuned to detect a single molecular species. Some examples include the receptors that mediate pheromone detection in insects, or those that function in neurotransmission.

The second approach, represented by the DNA sensors, is implemented by arrays of receptors with relatively broad responses. Here, specificity emerges from a constellation of receptor types that recognizes the molecule of interest. An example is the olfactory receptors in the main olfactory system of vertebrates.

This study not only highlights DNA’s potential for use in a novel and powerful odor detection system, but it also highlights its potential to play other novel roles in vivo, for example as a small molecule receptor, well outside of its familiar one as the repository of information in the genome.

Article: Thomas CL, Bayer EM, Ritzenthaler C, Fernandez-Calvino L, Maule AJ (2008) Specific targeting of a plasmodesmal protein affecting cell-to-cell communication. PLoS Biol 6(1): e7. doi:10.1371/journal.pbio.0060007