Dynamic imaging of molecular assemblies in live cells based on nanoparticle plasmon resonance coupling.
We used molecular-specific gold nanoparticles to monitor epidermal growth factor receptors (EGFR) in live A431 cells over time. Dark-field hyperspectral imaging, electron microscopy, and electrodynamic modeling were used to correlate optical properties of EGFR-bound plasmonic nanoparticles with receptor regulation state. We showed that receptor trafficking resulted in a progressive red shift of greater than 100 nm in the nanoparticle plasmon resonance wavelength over a time period of 60 min. Furthermore, we demonstrated that changes in peak scattering wavelengths of gold nanoparticles from 546 +/- 15 to 574 +/- 20, and to 597 +/- 44 nm are associated with EGFR trafficking from the cell membrane, to early endosomes, and to late endosomes/multivesicular bodies, respectively. Finally, we used the changes in scattering spectra of EGFR-bound nanoparticles and a straightforward statistical analysis of RGB-channel color images of labeled cells to create near real-time maps of EGFR regulatory states in living cells.
Aaron
Jesse
J
Department of Biomedical Engineering, Department of Physics, University of Texas at Austin, Austin, Texas 78712, USA.
Travis
Kort
K
Harrison
Nathan
N
Sokolov
Konstantin
K
D000818:Animals; D066246:ErbB Receptors / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D015603:Keratinocytes / Q000648:ultrastructure*; D053768:Metal Nanoparticles; D057054:Molecular Imaging; D020349:Surface Plasmon Resonance; D013499:Surface Properties
D006046:Gold; D066246:ErbB Receptors