Splicing exponential point spread function design for localization of nanoparticles.

Area of Science:

• Biophysics
• Optical Imaging
• Nanotechnology

Background:

• Accurate three-dimensional (3D) localization of nanoparticles is crucial for understanding biological processes at the nanoscale.
• Existing point spread functions (PSFs) often have limitations in adjustable detection range and spatial extent, hindering dense multi-particle imaging.
• Overlapping signals in dense imaging reduce localization accuracy and complicate data analysis.

Purpose of the Study:

• To propose a novel point spread function (PSF) for improved 3D nanoparticle localization.
• To demonstrate the tunability of the axial detection range and spatial extent of the proposed PSF.
• To validate the effectiveness of the designed PSF in dense multi-particle imaging and biological applications.

Main Methods:

• Development of a new PSF with adjustable design parameters for 3D localization.
• Comparative analysis of the designed PSF against existing PSFs for dense multi-particle imaging.
• Application of the PSF to record the 3D process of fluorescent microspheres penetrating a cell membrane.

Main Results:

• The proposed PSF allows simple adjustment of both axial detection range and spatial extent via design parameters.
• A PSF with a smaller spatial extent effectively reduced signal overlap in dense multi-particle imaging.
• Successful 3D recording of fluorescent microspheres penetrating HT-22 cell membranes was achieved.

Conclusions:

• The developed PSF offers significant advantages over existing methods for 3D nanoparticle localization.
• Tunable spatial extent is a key feature for reducing overlap and enhancing imaging of dense samples.
• The method is effective for visualizing dynamic biological processes at the cellular level.