Advancing the control of biochemical environments to study cellular responses
Yiqing Sun defended her PhD thesis at the Department of Mechanical Engineering on 16 June.
Cells in the human body constantly respond to signals from their surrounding environment. These signals include biochemical factors that guide essential processes such as cell growth, movement, and differentiation. In healthy tissues, these signals are tightly regulated, whereas in diseases such as cancer, they become highly abnormal and contribute to disease progression. Therefore, understanding how biochemical signals influence cells is crucial. In her PhD research, Yiqing Sun developed a microfluidic platform that can precisely control biochemical environments, making it easier to study and understand cellular responses.
In living organisms, many different factors interact closely, making it difficult to isolate individual effects. In vitro platforms offer greater control, but many existing approaches cannot accurately reproduce the dynamic and spatially complex nature of biochemical environments found in the body. To address this challenge, developed a microfluidic platform using magnetically driven artificial cilia. These tiny engineered structures actively generate and modulate fluid flows inside microchannels, allowing controlled delivery and removal of chemical signals.
Simulations and experiments
Sun began her research with the design and fabrication of the microfluidic system, integrating it with magnetic artificial cilia and an external actuation setup. A theoretical model was then developed to describe how the artificial cilia generate fluid motion in confined spaces. The model revealed non-intuitive flow behavior: when the tips of the magnetic artificial cilia are very close to the channel ceiling, flow reversal is predicted. This model was validated through simulations and experiments. Subsequently, the platform was applied to biological studies. Experiments demonstrated that it can rapidly create and remove localized chemical conditions. It was further used to study how cancer cells respond to gradients that guide cell movement.
Potential for the future
The results of this research provide a powerful tool for studying how cells respond to changing conditions. It has potential applications in cancer research, drug development, and tissue engineering in the future.
Title of PhD thesis: . Supervisors: Dr. and Prof. Jaap den Toonder.