Probing cell surface interactions using atomic force microscope cantilevers functionalized for quantum dot-enabled Forster resonance energy transfer

J Biomed Opt. 2009 Jul-Aug;14(4):040502. doi: 10.1117/1.3174429.


Forster resonance energy transfer (FRET) between quantum dot (QD) donors and red fluorescent protein (RFP)-tagged integrin acceptors in live cells is reported for the first time. A silica microsphere was coated with CdSeZnS QDs and mounted to the cantilever of an atomic force microscope (AFM). The QD microsphere is then conjugated with fibronectin to bind with RFP-alphav integrins expressed on the surface of HeLa cells. Following AFM-controlled cell contact with the QD-microsphere structure, FRET is observed between the QD-RFP pair using a photobleaching measurement technique. This FRET probe technique provides a novel tool for studying the cell surface receptor-ligand interactions in biomedical and biological research.

Publication types

  • Letter
  • Research Support, N.I.H., Extramural

MeSH terms

  • Cell Membrane / metabolism*
  • Fluorescence Resonance Energy Transfer / methods*
  • HeLa Cells
  • Humans
  • Membrane Proteins / metabolism*
  • Microscopy, Atomic Force / methods*
  • Protein Interaction Mapping / methods*
  • Quantum Dots*


  • Membrane Proteins