Sensing The Molecular World in Real Time Using Fluorescent and
Electrochemical Biomolecular Switches
Alexis Vallée-Bélisle, Francesco Ricci, Kevin Plaxco
Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106
Tel:805-893-5845 E-mail: email@example.com
Summary: I will explain how we design and build more efficient fluorescent and electrochemical biosensors based
on natural biomolecular switches.
All creatures, from bacteria to humans, must monitor their environments in order to survive. They do so with
biomolecular switches, made from RNA or proteins. Inspired by this natural technology, our laboratory has recently
developed several new artificial biosensors, which uses fluorescent of electronic biomolecular switches made from
nucleic acids, peptides or proteins to detect chemicals ranging from drugs to explosives to disease markers [1-2].
These sensors are reagentless, reusable, and selective enough to be employed in blood, soil and other grossly
contaminated materials. In my talk, I will explain how we design and build these new sensors and show how a better
understanding of natural biomolecular switches and their mechanisms of regulation (e.g. inhibition, activation, and
cooperativity) significantly helps our efforts to build a more efficient sensing technology.
Figure 1: Example of a bio-electronic switches for the real-time detection of cocaine in blood serum. An
electrochemical, aptamer-based switch that folds upon cocaine binding. Affixed via one terminus to an electrode and
modified at the other with a redox-active methylene blue molecule, the binding-induced folding of this aptamer
leads to a large increase in current, supporting the real-time detection of micromolar cocaine in blood serum as it
flows through the depicted, sub-microliter micro-fluidic device
 Vallée-Bélisle, A., Plaxco, KW, Curr. Opin. Struc. Biol. 20 (4), 518-26 (2010)
 Vallée-Bélisle, A., et al., Proc Natl Acad Sci U S A., 106 (33), 13802-7 (2009)