Compact on-chip fluorescence microscope for dynamic imaging of cellular processes and biomimetic systems

Area of Science:

• Biomedical Engineering
• Cellular Imaging
• Microscopy

Background:

• High-throughput fluorescence imaging is crucial for understanding dynamic cellular behavior in engineered tissues.
• Traditional microscopy methods require complex and expensive mechanical scanning systems.
• Cellular heterogeneity necessitates imaging multiple regions for representative biological data.

Purpose of the Study:

• To develop a compact, low-cost, on-chip fluorescence microscopy platform.
• To achieve high resolution and signal-to-noise ratio (SNR) without mechanical scanning.
• To enable wide-field monitoring of cellular dynamics in biomimetic and tissue-on-chip systems.

Main Methods:

• Integration of a 2D microlens substrate with a complementary metal-oxide-semiconductor sensor.
• Lateral excitation delivery with total internal reflection to minimize background noise.
• Optimization of optical geometry using analytical modeling and numerical simulations.

Main Results:

• Demonstrated cellular-level imaging of drug-induced oxidative stress and intracellular signaling in cancer cells.
• Visualized transport of molecules, nanoparticles, and ions across endothelial barriers in microfluidic co-cultures.
• Successfully studied complex interactions within tumor microenvironments using integrated microfluidic systems.

Conclusions:

• The developed on-chip microscope offers a simple, sensitive, and cost-effective solution for cellular imaging.
• It facilitates wide-field monitoring of large cell populations, capturing cell-to-cell variability.
• The platform supports diverse applications including drug screening, signaling studies, and tissue-on-chip research.