Autonomously oscillating soft actuators have been successfully obtained
by assembling pre-existing microgel particles. The amplitude of the
actuator’s oscillation could be controlled by selecting the types of
oscillations of constituent microelements, i.e., swelling–deswelling or
cooperative dispersing–flocculating motion of the microgels. The new
actuators prepared by this fabrication process make the oscillating
actuators suitable for practical use in microfluidic devices such as
The Ru(bpy)3 monomer was chosen as a catalyst for the chemical oscillating reaction named the Belousov–Zhabotinsky (BZ) reaction, which generates rhythmical redox changes from the oxidized Ru(III) state to the reduced Ru(II) state and vice versa.