Synchronization of chemo-mechanical oscillators

The synchronization of chemically driven oscillators plays a crucial role in various biological motions. An artificial model system of these chemo-mechanical oscillators is proposed in this study. The oscillator is composed of three liquid layers (oil/water/oil), which exhibit a back and forth motion in a glass tube. This motion is caused by the chemical reaction between a water-soluble surfactant and oil-soluble anions. The frequency is unique for an individual experimental setup because it depends on the surface state of the glass sensitively. When the glass tube with the liquid oscillator is placed on a plate with mechanical vibration, the frequencies of the oscillator and mechanical vibration become similar within a certain frequency range of mechanical vibration. When two or more glass tubes are placed in a boat floating on a water surface, all frequencies agree with each other by the joggling motion of the boat. The entrainment into the external vibration and mutual synchronization on the boat are explained by a simple mathematical model. The proposed chemo-mechanical oscillator may be used as a primitive model system for studying the interplay of macroscopic motion and molecular scale processes that control chemically driven motion.