Translating biomolecular recognition into nanomechanics

We report the specific transduction, via surface stress changes, of DNA hyb ridization and receptor-ligand binding into a direct nanomechanical respons e of microfabricated cantilevers. Cantilevers in an array were functionaliz ed with a selection of biomolecules. The differential deflection of the can tilevers was found to provide a true molecular recognition signal despite L arge nonspecific responses of individual cantilevers. Hybridization of comp lementary oligonucleotides shows that a single base mismatch between two 12 -mer oligonucleotides is clearly detectable. Similar experiments on protein A-immunoglobulin interactions demonstrate the wide-ranging applicability o f nanomechanical transduction to detect biomolecular recognition.