Urease stabilization in urea–urease–H+ system and its influence on the clock reaction dynamics

Abstract

The inherent autocatalytic kinetics of the urea–urease–H⁺ system positions it as a promising candidate for the design of dynamic materials with time-domain programmable functions. Nevertheless, the stability of the enzyme can markedly influence the temporal evolution dynamics of the system and curtail its widespread applicability. This work employs several kinds of enzyme stabilization methods, including chemical cross-linking, physical coating, solvent stabilization, and solvent-physical coating co-modification, to systematically explore the impact of enzyme stabilization on clock reaction dynamics. Extensive experimental tests and analysis indicate that solvent and chemical cross-linking stabilization methods can better preserve clock dynamics with sensitive switching ability. Nevertheless, due to significant pH changes in the reacting system, the reusability of the enzyme is better retained in the physical coating and solvent-physical coating co-modification methods.