Dual-Angle Interferometric Scattering Microscopy for Optical Multiparametric Particle Characterization
Journal article, 2024

Traditional single-nanoparticle sizing using optical microscopy techniques assesses size via the diffusion constant, which requires suspended particles to be in a medium of known viscosity. However, these assumptions are typically not fulfilled in complex natural sample environments. Here, we introduce dual-angle interferometric scattering microscopy (DAISY), enabling optical quantification of both size and polarizability of individual nanoparticles (radius <170 nm) without requiring a priori information regarding the surrounding media or super-resolution imaging. DAISY achieves this by combining the information contained in concurrently measured forward and backward scattering images through twilight off-axis holography and interferometric scattering (iSCAT). Going beyond particle size and polarizability, single-particle morphology can be deduced from the fact that the hydrodynamic radius relates to the outer particle radius, while the scattering-based size estimate depends on the internal mass distribution of the particles. We demonstrate this by differentiating biomolecular fractal aggregates from spherical particles in fetal bovine serum at the single-particle level.

nanoparticles

holography

aggregates

size

morphology

iSCAT

Author

Erik Olsén

Chalmers, Physics, Nano and Biophysics

Berenice García Rodríguez

University of Gothenburg

Fredrik Skärberg

University of Gothenburg

Petteri Parkkila

Chalmers, Physics, Nano and Biophysics

Giovanni Volpe

University of Gothenburg

Fredrik Höök

Chalmers, Physics, Nano and Biophysics

Daniel Sundås Midtvedt

University of Gothenburg

Nano Letters

1530-6984 (ISSN) 1530-6992 (eISSN)

Vol. 24 6 1874-1881

Subject Categories

Atom and Molecular Physics and Optics

DOI

10.1021/acs.nanolett.3c03539

More information

Latest update

3/7/2024 9