A facile strategy to construct MOF-based nanocatalyst with enhanced activity and selectivity in oxytetracycline degradation

Recently, many efforts have been dedicated to construct artificial catalysts with enzyme-like activity. However, it is still a big challenge to endow artificial catalysts with specific substrate selectivity. In this study, we developed a facile strategy to construct a MIL-53(Fe)-based nanocatalyst with designable selectivity in the degradation of oxytetracycline (OTC). Through the Fe–O–P conjunction, oxytetracycline aptamer (OA) can be easily anchored on MIL-53(Fe) to provide the specific site for OTC binding. We verified that the obtained MIL-53(Fe)-Apt nanocatalyst displayed enhanced catalytic ability in the degradation of OTC, whereas obvious suppression toward other substrate analogues. This performance therefore brings about an anticipated selectivity toward OTC. Moreover, we highlighted that the configuration of aptamers on MIL-53(Fe) can be modulated through varying conjunction mode. Structure–function analysis revealed that aptamer configuration affects the local concentration of substrate around catalytic site, which thus decides the catalytic performance toward OTC. This work presented a facile and promising strategy for developing artificial catalysts with designable selectivity.