Assessing Hydrolytic Activity of Surfactant-Based Nanozymes: Methodological and Kinetic Considerations

The review critically discusses the methodological approach used to characterize the mechanism and to assess kinetic parameters in catalytic processes promoted by surfactant-based nanozymes. Using the hydrolysis of carboxylic and phosphoric esters as model reactions, it quantitatively analyzes several examples in which the catalytic system consists either of aggregates formed by non-functional surfactants or of surfactants bearing one or more reactive functions, ranging from classical nucleophiles to transition metal ions. This analysis highlights both the importance of the design of the kinetic experiments and of the selection of the appropriate experimental conditions, and the need to apply the correct model and set of kinetic equations in the interpretation of the data, in order to obtain kinetic parameters with true chemical significance. Improper kinetic modeling may lead to misleading rate enhancements and false claims of very high activity of the system studied. The aim of the review is not to provide a general overview of micelle and liposome-promoted catalysis, but rather to offer methodological tools to correctly assess rate accelerations with these systems.