Super-resolution three-dimensional fluorescence and optical diffraction tomography of live cells using structured...

Area of Science:

• Biophysics
• Cell Biology
• Optical Imaging

Background:

• Accurate measurement of intracellular components is crucial for understanding cell dynamics.
• Existing methods for 3D refractive index (RI) and fluorescence imaging often face limitations in speed, stability, or resolution.

Purpose of the Study:

• To develop and validate a multimodal imaging technique integrating optical diffraction tomography (ODT) and 3D structured illumination microscopy (SIM).
• To enable simultaneous, high-resolution 3D mapping of refractive index and fluorescence distributions within live cells.

Main Methods:

• Utilized a digital micromirror device to generate structured illumination patterns for both ODT and SIM, ensuring rapid and stable data acquisition.
• Applied the combined ODT-SIM approach to image fluorescent beads and live HeLa cells, capturing dynamic intracellular processes.
• Employed spatiotemporal correlation analysis to track the trajectory of fluorescent beads within cells.

Main Results:

• Successfully measured the 3D refractive index distribution and 3D fluorescence images of various samples, including fluorescent bead clusters.
• Monitored the time-lapse 3D refractive index dynamics of fluorescent beads within a HeLa cell.
• Analyzed bead trajectories, demonstrating the method's capability for live-cell dynamics studies.

Conclusions:

• The multimodal ODT-SIM approach offers a powerful tool for comprehensive 3D characterization of live cells.
• This technique facilitates the study of intracellular dynamics and component behavior with high spatial and temporal resolution.
• The method's stability and speed make it suitable for investigating complex biological processes.