Nano-level position resolution for particle tracking in digital in-line holographic microscopy

Area of Science:

• Biophysics
• Microscopy
• Biotechnology

Background:

• Three-dimensional particle tracking is crucial in biology.
• Digital in-line holographic microscopy (DIHM) is a powerful technique for particle tracking.
• Speckle noise, out-of-focus signals, and twin images hinder DIHM accuracy.

Purpose of the Study:

• To enhance 3D particle tracking in DIHM by reducing noise and improving reconstruction.
• To introduce an adaptive noise reduction method for DIHM.

Main Methods:

• Implemented an adaptive noise reduction method using bidimensional ensemble empirical mode decomposition (BEMD).
• Applied BEMD to eliminate speckle noise and background adaptively in holograms.
• Utilized a 3D deconvolution approach for effective particle feature identification during reconstruction.

Main Results:

• The adaptive noise reduction method effectively eliminated speckle noise and background.
• Combined BEMD with 3D deconvolution for improved particle feature identification.
• Achieved high-resolution 3D particle tracking with resolution approaching 2 nm axially and 1 nm transversely.

Conclusions:

• The developed method significantly improves the accuracy and resolution of 3D particle tracking using DIHM.
• This technique has potential applications in studying living cells and single molecules.
• Enhanced DIHM facilitates advancements in biological research requiring precise particle localization.