Enzyme-Powered Porous Micromotors Built from a Hierarchical Micro- and Mesoporous UiO-Type Metal–Organic Framework

Abstract

Enzyme-powered porous micro-and nanomotors combine self-propelled motion with tailored functionalities like adsorption and release, making them very attractive for myriad applications. Here, we report the design, synthesis and functional testing of enzyme-powered porous micromotors built from a metal-organic framework (MOF). We began by subjecting a pre-synthesized microporous UiO-type MOF to ozonolysis, to confer it with mesopores sufficiently large to adsorb and host the enzyme catalase (size: 6-10 nm). We then encapsulated catalase inside the newly-formed mesopores, observing that they are hosted in those mesopores located at the subsurface of the MOF crystals. In the presence of H2O2 fuel, our MOF motors (or MOFtors) exhibit jet-like propulsion enabled by enzymatic generation of oxygen bubbles. Moreover, thanks to their hierarchical pore system, the MOFtors retain sufficient free space for adsorption of additional targeted species, which we validated by testing a MOFtor for removal of the pollutant Rhodamine B during self-propulsion in water. Our findings will encourage future designs of porous MOF-based micro-and nanomotors for delivery, sorption and catalytic applications.

Sustainable One-Pot Immobilization of Enzymes in/on Metal-Organic Framework Materials

“…Crucially, these highly porous MOFs could initially only be attained with the use of very long linkers, resulting in generally unstable systems. In this context, Yang et al proposed the idea of subjecting the MOF to ozonolysis to generate mesopores wide enough for catalase immobilization [23].…”

Towards micromachine intelligence: potential of polymers

“…The retained free space was also used for the adsorption removal of Rhodamine-B during the self-propulsion. 49 Pumera et al recently reported rod-like MOF microrobots for the removal of radioactive species in water. 50 The latter were developed by selectively depositing Pt on one side of the rods pre-synthesized through membrane-based interfacial reaction (Fig.…”

Specific Screening of Prostate Cancer Individuals Using an Enzyme-Assisted Substrate Sensing Platform Based on Hierarchical MOFs with Tunable Mesopore Size

“…Thanks to the open mesochannels and designable topology, full advantages of hierarchical mesoporous Zr-based metal–organic frameworks (mesoMOFs) could be taken for constructing such a heterogeneous system. − Their rigid and stable mesochannels could work as exoskeletons to immobilize and protect natural SOX. − Meanwhile, the phosphorescent carboxylated metalloporphyrin of TCPP-Pt could serve as colinker to be well incorporated into the surrounding microporous walls as oxygen-sensitive signal units (Scheme ). Metallic nodes in MOFs could effectively isolate TCPP-Pt, thus avoiding the aggregation-induced quenching effect .…”