High speed two-photon laser scanning stereomicroscopy for three-dimension tracking multiple particles simultaneously...

Area of Science:

• Biomedical Optics
• Microscopy
• Nanotechnology

Background:

• Accurate three-dimensional (3D) particle tracking is crucial for understanding dynamic processes in biological and material sciences.
• Traditional methods often face limitations in speed and penetration depth, especially in scattering media.

Purpose of the Study:

• To introduce a novel video-rate two-photon laser scanning stereomicroscope for high-speed, 3D particle tracking.
• To demonstrate its capability for imaging nanoparticle transport in challenging, light-scattering environments.

Main Methods:

• Implementation of a resonant galvanometer for high-speed volumetric imaging (30 volumes/sec, 512x512 pixels).
• Utilized pulse multiplexing and demultiplexing techniques for rapid switching between parallax views (nanosecond timescale).
• Two-photon excitation for deep tissue penetration and scattering media imaging.

Main Results:

• Achieved volumetric imaging speeds of 30 volumes per second.
• Demonstrated nanoparticle tracking in 1% intralipid solution and fibrillar scaffolds.
• Attained a tracking penetration depth of approximately 400 μm in scattering media.

Conclusions:

• The developed microscope offers unprecedented speed and depth for 3D particle tracking.
• Enables the study of fast transport phenomena in complex biological and material systems.
• Represents a significant advancement for in-situ analysis of nanoparticle dynamics.