Non-autonomous zinc-methylimidazole oscillator and the formation of layered precipitation structures in a hydrogel

Oscillations are one of the intrinsic features of many animate and inanimate systems. The oscillations manifest in the temporal periodic change of one or several physical quantities describing the systems. In chemistry and biology, this physical quantity is the concentration of the chemical species. In most chemical oscillatory systems operating in batch or open reactors, the oscillations persist because of the sophisticated chemical reaction networks incorporating autocatalysis and negative feedback. However, similar oscillations can be generated by periodically changing the environment providing non-autonomous oscillatory systems. Here we present a new strategy for designing a non-autonomous chemical oscillatory system for the zinc-methylimidazole. The oscillations manifested in the periodic change of the turbidity utilizing the precipitation reaction between the zinc ions and 2-methylimidazole (2-met) followed by a partial dissolution of the formed precipitate due to a synergetic effect governed by the ratio of the 2-met in the system. Extending our idea spatiotemporally, we also show that these precipitation and dissolution phenomena can be utilized to create layered precipitation structures in a solid agarose hydrogel.

Automated summary

Oscillations are an intrinsic feature of many systems, both animate and inanimate, and can be manifested as a periodic change in physical quantities such as concentration. In this study, we present a new strategy for designing a non-autonomous chemical oscillatory system by periodically changing the environment. By utilizing a precipitation reaction and the subsequent partial dissolution of the formed precipitate, we demonstrate the generation of oscillations in the turbidity of the system. Furthermore, we show that these phenomena can be used to create layered precipitation structures in a solid agarose hydrogel.