Cell-sized enzyme-powered motors made by microfluidic assembly

This thesis addresses the fundamental questions surrounding the design and functional capabilities of enzyme-powered motors synthesized using microfluidic techniques. Inspired by the motion of biological cells, the research focuses on the development of motors prepared from artificial cell (protocell) scaffolds, investigating their propulsion mechanisms, motion directionality, and collective behavior. The thesis first presents new microfluidic methods based on a glass capillary device for the synthesis of polymer and polymer-protein-based protocells. This platform enables precise control over their size, composition, and functional properties, demonstrating its versatility in the fabrication of complex microstructures. Next, a novel approach for creating urease-powered micromotors using double emulsion-templated microcapsules is presented. The study explores how surfactants used during emulsion assembly that integrate themselves into the resultant microcapsule structure can reliably lead to autonomous motion, providing insights into the design principles that govern the efficiency of enzyme-powered motors prepared by droplet microfluidics. The thesis next investigates the directed motion of urease-powered motors in gradients of urea, revealing how these motors can be directed away from high concentrations of substrate, highlighting our ability to control their motion in complex fluids. Finally, the thesis explores interactions between enzyme-powered (active) and passive particles, demonstrating how active particles can enhance the motion of passive ones in their vicinity. The findings of this dissertation significantly advance our understanding of enzyme-powered motors, offering new strategies for their design and application. The use of microfluidic technology for the synthesis of these motors opens up new possibilities for the precise control of their properties, paving way for their use in a range of scientific and technological applications.