Combining AFM and FRET for studies at the cellular level

We report on the development of a Forster resonance energy transfer (FRET) enabled atomic force microscope (AFM) for the study of biomechanics and mechanobiology at the cellular level. The hybrid microscopy system combines the spatial resolution and control of the AFM with the nanoscale sensing capabilities of FRET to enable simultaneous detection of cell mechanical responses and correlation of those responses with cellular biochemistry. Here, we show FRET signal from donor-coated microspheres, that are attached to an AFM cantilever, to acceptor-labeled integrins in a fixed cell system. Additionally, we demonstrate and discuss the attachment of quantum dots to silica microspheres as the FRET donor.

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