Exploiting Dynamic Nonlinearity in Upconversion Nanoparticles for Super-Resolution Imaging

Area of Science:

• Nanotechnology
• Microscopy
• Optics

Background:

• Single-beam super-resolution microscopy, or superlinear microscopy, utilizes nonlinear probe responses in confocal microscopy.
• This technique offers simplicity, avoiding specialized equipment or beam manipulation.

Purpose of the Study:

• To enhance the spatial resolution of single-beam super-resolution microscopy.
• To introduce a method for dynamic optical nonlinearity in fluorescent probes.

Main Methods:

• Modulating excitation intensity during image acquisition to induce dynamic optical nonlinearity.
• Utilizing upconversion nanoparticles (UCNPs) as fluorescent probes.
• Applying a weighted finite difference imaging algorithm to extract higher-order fluorescence responses.

Main Results:

• Achieved a spatial resolution of 132 nm for resolving single nanoparticles.
• Demonstrated improved resolution beyond standard superlinear microscopy.
• Successfully applied the technique over a large imaging area.

Conclusions:

• The proposed method offers a significant enhancement in super-resolution microscopy.
• Dynamic nonlinear fluorescent probes present a promising avenue for advanced nanoscopy.
• This approach provides a new strategy for achieving higher resolution in super-resolution imaging.