Yukuan Yu

Date of Award

Spring 2023

Document Type

Open Access Thesis


Biomedical Engineering

First Advisor

Guiren Wang


Understanding the function of aquaporins in transcellular transport is vital for homeostasis, pathophysiology, and translational potential in AQP-based diagnostics and therapeutics. Microfluidics device has the potential to evaluate the function of aquaporins with precise control and manipulate micro-scale fluid due to good optical quality and short processing distance. This work has two parts: cell culture in a microfluidic chip to characterize aquaporins’ function and visualization of single cell volume change under osmotic pressure shock in a homemade imaging dish. For the first part, we established a microfluidics platform for future modification and measurement of the dynamic volume change of biological cells. Then, we used the layer-by-layer method to microfabricate the microfluidics device made of acrylic plates and pressure-sensitive adhesive. It is easier to make simple-patterned microchannels and provide better optical quality for bioimaging by attaching a thin microscope coverslip. MDA-MB-231 breast cancer cell line was used for this study. When culturing cells in microfluidics devices, we improved the coating method to ensure the cells attach to the microchannel wall. Meanwhile, reducing the flow of culture medium inside the chamber can improve cell growth in an incubator. Our results showed that MDA-MB-231 could grow well in our microfluidics platform.

For the second part, we used a microinjection system to study the cell volume change caused by water flux through the plasma membrane of a single cell under osmotic pressure shock. The dynamics of cell volume change were visualized and measured using a microscope with an oil immersion objective and ImageJ. The change in cell volume was monitored and measured in our system with a corresponding reduction of environmental osmotic pressure. This research confers new opportunities when utilized in monitoring and measuring transcellular transport phenomena of a single cell for in-vitro experiments.