High-resolution multi-modal imaging of sub-cellular structures with low numerical aperture objective.

Area of Science:

• Biomedical Imaging
• Microscopy Technology
• Cell Biology

Background:

• High numerical aperture (N.A.) objectives are essential for subcellular imaging but are costly, complex, and have limited fields of view.
• Current microscopy methods often require oil immersion and are restricted to imaging only a few cells at a time.

Purpose of the Study:

• To develop a cost-effective and accessible method for high-resolution imaging of subcellular structures using low N.A. objectives.
• To demonstrate simultaneous capture of scattering, phase, and fluorescence images with sub-diffraction-limited resolution.

Main Methods:

• Utilized a 2-dimensional (2-D) microlens substrate in close proximity to the sample.
• Leveraged the efficient collection of evanescent waves containing high-frequency information.
• Employed a low N.A. objective (0.25 N.A.) for imaging breast cancer cells (BT-20).

Main Results:

• Achieved sub-diffraction-limited resolution (<400 nm) with a low N.A. objective.
• Successfully observed subcellular structures and nanoparticle uptake in breast cancer cells.
• Demonstrated simultaneous capture of scattering, phase, and fluorescence images.

Conclusions:

• Microlens-assisted imaging offers an easy-to-implement, cost-effective solution to enhance resolution in microscopes with low N.A. objectives.
• This technology can lead to affordable, portable multi-modal imaging systems.
• Broad implications for democratizing high-quality microscopy, especially in resource-limited settings.