Optically computed phase microscopy for quantitative dynamic imaging of label-free cells and nanoparticles

Area of Science:

• Biophysics
• Nanotechnology
• Optical Imaging

Background:

• Nanoparticle-based drug delivery systems, including those in COVID-19 vaccines, are increasingly prevalent.
• Understanding cell-nanoparticle mechanical interactions is vital for improving drug delivery system efficacy and safety.

Purpose of the Study:

• To introduce and validate a novel imaging technique, optically computed phase microscopy (OCPM), for tracking nanoscale motion.
• To demonstrate OCPM's capability in quantitatively imaging the dynamic interactions between cells and nanoparticles.

Main Methods:

• Investigated optically computed phase microscopy (OCPM), a technique processing 3D spatial-spectral data via optical computation.
• Utilized OCPM to track the motion of transparent cells and nontransparent nanoparticles with nanometer displacement sensitivity.
• Mechanically excited magnetic nanoparticles using an external magnetic field to observe their motion.

Main Results:

• OCPM successfully imaged the motion of cells and magnetic nanoparticles with high spatial and temporal resolution.
• Demonstrated nanometer displacement sensitivity in tracking particle and cell movements.
• Quantitatively captured the dynamic en face plane motion of nanoparticles under external magnetic stimulation.

Conclusions:

• Optically computed phase microscopy (OCPM) is a powerful tool for quantitative imaging of nanoscale mechanical interactions.
• OCPM advancements are critical for the development of safer and more effective nanoparticle drug delivery systems.
• This technology enables precise tracking of cell and nanoparticle dynamics, paving the way for improved nanomedicine.