Shape-controlled movement of Zn/SU-8 micromotors†

Abstract

Creating micromotors (MMs) that will have the highest possible velocities has become one of the main focuses in the field of autonomous microdevices research. The importance of velocity stems from various autonomous microdevices applications, ranging from faster drug delivery to the eradication of various bacterial biofilms using only mechanical movement. To investigate how different shapes affect the velocity of Zn/SU-8 micromotors in acid solution, we fabricated micromotors with various geometries (Zn/SU-8/Cylindrical, Zn/SU-8/Rectangular cuboid, Zn/SU-8/Triangular prism, Zn/SU-8/Pentagonal prism and Zn/SU-8/Pentagrammic prism MMs). This is the first comparative study where shape has been isolated as the critical factor influencing micromotor velocity under the same catalytic surface conditions. Our results demonstrate that Zn/SU-8/Rectangular cuboid and Zn/SU-8/Triangular prism MMs exhibit significantly higher average velocities compared to the other studied MMs. The shape-optimized Zn/SU-8 micromotors, characterized by their simple synthesis process and low cost, offer significant potential to enhance efficiency and navigation in both environmental and medical applications through precise movement control.