High-Throughput, High-Resolution Interferometric Light Microscopy of Biological Nanoparticles

Area of Science:

• Biophysics
• Optical Microscopy
• Nanotechnology

Background:

• Label-free microscopy is crucial for biological nanoparticle (BNP) imaging.
• Conventional methods struggle with low contrast and limited spatial resolution for BNPs.
• Interferometric microscopy improves contrast but lateral resolution remains a challenge.

Purpose of the Study:

• To develop a label-free, high-resolution imaging technique for BNPs.
• To achieve a 2-fold lateral resolution improvement over a large field-of-view.
• To enable high-throughput morphological characterization of diverse BNPs.

Main Methods:

• Wide-field interferometric microscopy combined with computational imaging.
• Vectorial-optics-based forward model for image reconstruction.
• Partially coherent asymmetric illumination for enhanced resolution.

Main Results:

• Achieved ~150 nm lateral resolution over a >100x100 μm² field-of-view.
• Enabled simultaneous imaging of over 10^4 BNPs without labels or preparation.
• Demonstrated high-throughput morphological visualization of Ebola virus-like particles and vaccine candidates.

Conclusions:

• The developed technique offers a low-cost, robust platform for label-free imaging of BNPs.
• Provides high-throughput and high-resolution characterization of a broad size range of BNPs.
• Advances the study of nanoparticle morphology and structure in biological systems.