Ayusman SenDepartments of Chemistry & Chemical Engineering
Pennsylvania State University
Self-propelling Macro-scale Sheets Powered by Enzymes
Harvesting chemical energy from molecular level catalysis to actuate motion at the macroscale is a scientific grand challenge. Chemically powered, enzymatic micro-pumps are biocompatible and highly selective and have been shown to direct ambient flows and transport suspended cargo. Through experiments and simulations, we show that enzymatic pumping can be used for directed linear and rotary motion of centimeter-scale polymer sheets. Asymmetric coating of the enzymes on polymer sheets induces vectorial reaction-induced buoyancy-driven flows that propel the sheets. The directionality and speed of the sheets can be easily manipulated by changing the coating symmetry, the type of enzyme, and the substrate concentrations. We demonstrate complex motion behavior of sheets including linear and rotary motion in opposite directions. This work demonstrates the use of enzymes for macroscale robotics. Because of their biocompatibility, the enzymatic actuation can also find in vivo applications.