Light scattering microscopy measurements of single nuclei compared with GPU-accelerated FDTD simulations

Area of Science:

• Biophysics
• Optical Microscopy
• Computational Modeling

Background:

• Standard Mie models for homogeneous spheres are inadequate for analyzing complex biological structures like cell nuclei.
• Understanding light scattering by cell nuclei is crucial for advanced microscopy techniques.

Purpose of the Study:

• To investigate single cell nuclei using advanced scattering microscopy.
• To develop and apply a more accurate computational model for analyzing nuclear scattering patterns.
• To understand the influence of nuclear micro- and nanostructure on scattering.

Main Methods:

• Utilized two-dimensional angularly and spectrally resolved scattering microscopy.
• Implemented an accelerated finite-difference time-domain (FDTD) method on a graphics processor unit (GPU) with domain decomposition.
• Modeled cell nuclei as spheres with randomly distributed internal inclusions representing chromatin and nucleoli.

Main Results:

• Demonstrated the insufficiency of the standard Mie model for homogeneous spheres.
• Achieved qualitative agreement between experimental and theoretical scattering spectra using the heterogeneous nuclear model.
• Showcased the significant impact of nuclear micro- and nanostructure on scattering patterns.

Conclusions:

• Heterogeneity, including nucleoli and chromatin, significantly influences light scattering by cell nuclei.
• Advanced computational methods like GPU-accelerated FDTD are essential for accurate analysis of biological scattering data.
• This study provides a more refined approach to interpreting scattering microscopy data from cell nuclei.