Light-Triggered Accelerated Degradation of Surface-Bound Chemical Agents

The critical need to decontaminate surfaces from highly toxic chemical warfare agents (CWA) and the complexity of interfacial domains underscore the challenges associated with developing efficient surface cleanup technologies. To address these challenges and needs, we describe a light-switchable surface targeting microrobotic decontamination platform for accelerated biocatalytic degradation of surface-bound CWA. Biohybrid microrobots, based on Chlamydomonas reinhardtii algae, functionalized with the organophosphate-degrading enzyme phosphotriesterase (PTE), are shown to display unique light-switchable surface adhesion and gliding behaviors to offer an extremely efficient and fast surface decontamination. These biohybrid algae-PTE microrobots reversibly target hard-to-reach contaminated surfaces under blue light irradiation, while red light triggers their transition back to the bulk solution. In the surface-bound state, PTE-functionalized algae can glide collectively across the contaminated surface toward enhanced degradation efficiency. Upon completing the surface decontamination, the algae-PTE microrobots are easily released from the surface by switching to red irradiation. The applicability of the light-switchable microrobotic platform is demonstrated using a variety of contaminated surfaces, including fabrics, skin, and irregular solid surfaces, displaying surface-decontamination efficiencies higher than 90% within 5 min. Such highly efficient and rapid light-switchable surface targeting biocatalytic microrobotic platform holds considerable promise for diverse environmental surface remediation applications.