Interfacial tension driving movement in soft matter systems
Movement, shape change, and adaptability are key features of living systems, enabling cells to interact with and respond to their environment. In her PhD research, Chanikan Wongkaew investigated how interfacial tension, the force that shapes droplets and bubbles, can be transformed from a passive physical constraint into an active design principle for creating life-like behaviors in soft materials.
Wongkaew developed minimal synthetic models where interfacial tension couples with molecular chirality and chemical reactions to drive dynamic processes. For example, by reducing interfacial tension and inserting light-responsive molecules, spherical droplets could reversibly transform into branched or helical shapes, mimicking cellular protrusions. In another system, molecular motors powered by light triggered chirality inversion in liquid crystal droplets, where handedness switched dynamically and propagated from the molecular to the microscopic scale. Finally, Wongkaew demonstrated how chemical reactions that generate amphiphiles could produce evolving micelles and vesicles, which in turn fueled autonomous droplet motion through interfacial tension gradients.
These studies show that interfacial tension is not merely a background constraint but a powerful driver of motion, adaptability, and self-organization. By coupling simple physical principles to molecular design, synthetic droplets can reproduce life-like dynamics such as shape morphing, chirality switching, and self-propulsion. Beyond fundamental insights, this research opens pathways toward applications in synthetic cells, adaptive biomaterials, soft robotics, and nanomedicine, fields where materials that can move, reshape, or respond to stimuli are increasingly valuable.