Robust Determination of the Anisotropic Polarizability of Nanoparticles Using Coherent Confocal Microscopy
- 详细技术说明
- This invention is a technique to identify shapes inferred from scattering properties of nanoparticles with no prior knowledge of the shapes.
- *Abstract
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It is currently difficult to determine the shapes of nanoparticles. Current methods rely on fluorescence or Raman-spectroscopy, yet these methods are not always reliable, especially in high-noise environments, and they do not offer a three-dimensional characterization of the nanoparticle.
This invention is a technique to identify shapes inferred from scattering properties of nanoparticles with no prior knowledge of the shapes.
DESCRIPTION/DETAILS
This technique includes a modification of a coherent confocal microscope device, as well as an algorithm to analyze the microscopes observations.
A coherent confocal microscope device is equipped with a beam shaper that controls polarity of the incident beam. Interference with a reference beam allows the collection of data sensitive to an electric field. A high aperture lens gives many propagation directions and therefore many polarization states in the field.
The field in the focal region is found by integrating the incident rays in an angular spectrum. The resulting focal fields display significant fields in all directions. The scattered field can then be propagated back to the detector. Diverse PSFs/OTFs mean each component of the polarizability produces a different signature in the data. Assuming a single isolated scatterer, the polarizability and position can be estimated by minimizing a cost function. Near the focal plane, each OTF can be approximately characterized by one magnitude and one phase function.
The approximation makes it easy to repeatedly calculate the cost. A Nelder-Mead algorithm is used to iteratively minimize over the three position variables.
APPLICATIONS
This invention can determine shapes at the virus level and distinguish between different viruses for screening purposes; drug delivery nano particle quality control; imaging agent manufacture quality control.
BENEFITS
- Full polarizability measurement removes assumptions about particle shape;
- Wide aperture lens and beam shaping detects significant fields in all directions in a single image; and
- Algorithmic component to process results using a cost function accurately estimates position and polarizability of the nanoparticles, even in noisy environments.
For more information about this technology, please contact the University of Illinois at Urbana-Champaign Office of Technology Management at otm@illinois.edu.
- 国家/地区
- 美国
