A mechanical bond that turns a magnetic resonance signal on when it finds what it is looking for.
Hyperpolarized xenon can be made to report on its surroundings, but only if something gates its access to a molecular cage. We used a rotaxane to do the gating: thread the axle and the cage is silenced, cut the thread and the signal switches on.
Because the thread can be a peptide, the switch becomes a detector. An enzyme cuts it, and the contrast agent announces that the enzyme was there. A molecular machine doing diagnostics.
Carson J. Bruns, Associate Professor, ATLAS Institute and the Paul M. Rady Department of Mechanical Engineering, University of Colorado Boulder.
Carson J. Bruns