Imaging individual proteins and nanodomains on intact cell membranes with a probe-based optical antenna.
Optical antennas that confine and enhance electromagnetic fields in a nanometric region hold great potential for nanobioimaging and biosensing. Probe-based monopole optical antennas are fabricated to enhance fields localized to <30 nm near the antenna apex in aqueous conditions. These probes are used under appropriate excitation antenna conditions to image individual antibodies with an unprecedented resolution of 26 +/- 4 nm and virtually no surrounding background. On intact cell membranes in physiological conditions, the obtained resolution is 30 +/- 6 nm. Importantly, the method allows individual proteins to be distinguished from nanodomains and the degree of clustering to be quantified by directly measuring physical size and intensity of individual fluorescent spots. Improved antenna geometries should lead to true live cell imaging below 10-nm resolution with position accuracy in the subnanometric range.
van Zanten
Thomas S
TS
BioNanoPhotonics Group, IBEC-Institute for Bioengineering of Catalonia and CIBER-bbn, Baldiri Reixac 15-21, Barcelona, Spain.
Lopez-Bosque
Maria J
MJ
Garcia-Parajo
Maria F
MF
D000906:Antibodies / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000378:metabolism; D017261:Glycosylphosphatidylinositols / Q000378:metabolism; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D016169:Lymphocyte Function-Associated Antigen-1 / Q000378:metabolism; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D015335:Molecular Probes / Q000378:metabolism*; D009000:Monocytes / Q000166:cytology* / Q000378:metabolism; D049329:Nanostructures / Q000737:chemistry*; D055620:Optical Phenomena; D011506:Proteins / Q000378:metabolism*
D000906:Antibodies; D005456:Fluorescent Dyes; D017261:Glycosylphosphatidylinositols; D016169:Lymphocyte Function-Associated Antigen-1; D015335:Molecular Probes; D011506:Proteins