Accession Number:



Double Helix SPINDLE Module for 3-D Super-resolution Imaging of Nanoscale Plasmon-enhanced Photocatalysis

Descriptive Note:

[Technical Report, Final Report]

Corporate Author:

Cornell University

Personal Author(s):

Report Date:


Pagination or Media Count:



This DURIP grant enabled us to acquire an addon equipment module, Double Helix SPINDLE, to our existing optical microscope to enable 3D singlemolecule superresolution fluorescence imaging, with nanometer resolution in x, y, and z dimensions, beyond our original 2D imaging of comparable resolution. This would allow us to study reactions on catalyst particles with complex 3D morphologies, such as those semiconductor particles with truncated bipyramidal morphologies and those with additional plasmonic particles deposited on top. This double Helix module has been purchased, installed on our microscope for singlemolecule superresolution imaging, tested and calibrated for xyz single-molecule localization to 20 nm precision. Although powerful in resolving singlemolecule targets in 3D with high resolution, it comes with additional complications technically. First, as this module is added in the detection path and the module contains a phase mask and multiple lens for light collimation and refocus, the overall light throughput is decreased, compromising some detection sensitivity in singlemolecule imaging. Second, due to the double helix point spread function, the image of a single molecule appears as two lobes with differentalignments for different z positions, as compared with a single Gaussianshaped image in typical 2D imaging. This difference in image properties made our homewritten MATLAB code unsuitable for automated data processing, which are absolutely necessary because a typical day of experiments in our lab generates tens to hundreds of thousands of images. On the other hand, the ImageJ plug in that was provided by the vendor has very limited automation function and not open source for revision. We need a graduate student or postdoc, who is an excellent computer programmer and also has a project focused on 3D imaging to justify devoting sufficient time to work out another 3D version of our home-written codes.

Subject Categories:

  • Optics
  • Test Facilities, Equipment and Methods

Distribution Statement:

[A, Approved For Public Release]