Dual-enzyme natural motors incorporating decontamination and propulsion capabilities

Abstract

Self-propelled dual-function biocatalytic motors, consisting of unmodified natural tissue and capable of in-motion bioremediation, are described. These enzyme-rich tissue motors rely on the catalase and peroxidase activities of their Raphanus sativus radish body for their propulsion and remediation actions, respectively. The continuous movement of the biocatalytic tissue motors through the contaminated sample facilitates the dynamic removal of phenolic pollutants. Hydrogen peroxide plays a dual role in the propulsion and decontamination processes, as the motor fuel and as co-substrate for the phenol transformation, respectively. Localized fluid transport and mixing, associated with the movement of the radish motors and corresponding generation of microbubbles, greatly improve the remediation efficiency resulting in maximal removal of pollutants within 3 min. The new ‘on-the-fly’ remediation process is cost effective as it obviates the need for expensive isolated enzymes and relies on environmental-friendly plant tissues.