Conformational Control of Energy Transfer: A Mechanism for Biocompatible Nanocrystal-Based Sensors


  • E.R.K. was supported by The Royal Commission for the Exhibition of 1851. The work received support from the NIH through grants 5-U54-CA151884-03 (M.G.B.) and 5R01CA126642-02 (M.G.B., D.G.N). The Biophysical Instrumentation Facility for the Study of Complex Macromolecular Systems and DCIF at MIT (NSF-0070319, NIH GM68762 and CHE-980806, DBI-979582) are gratefully acknowledged.


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Know when to fold 'em: Combination of a pH-triggered oligonucleotide conformational switch with fluorescent nanocrystals gives a sensitive pH nanosensor (see scheme). Analyte-dependent conformational changes control the distance between the nanocrystal energy donor (green) and a FRET acceptor (red), which results in a reporter for pH values in individual endosomes of living cells.