Application of metal-organic framework (MOF)-based enzymatic amplification strategy for the sensitive electrochemical detection of tuberculosis

Herein, a small molecule, hemin/G-quadruplex (G4-hemin), was physically embedded into NH 2 -MIL-53 (Al) to construct a novel metal-organic framework (MOF)-based enzyme ( [email protected] ). Its catalytic activity and stability were investigated in detail by catalyzing a reaction of 3,3′,5,5′-Tetramethylbenzidine (TMB) in the presence of H 2 O 2 . The results show that the activity and stability of this new enzyme is better than that of traditional hemin or G4-hemin, and even stronger than that of [email protected] ( [email protected]  > G4-hemin >  [email protected]  > hemin). No significant loss in catalytic activity was observed for at least one day. Even after eight days, only a 13.8 % decrease in activity was recorded. An electrochemical biosensor was successfully developed based on a signal amplification strategy utilizing the catalysis of [email protected] The sensor was able to sensitively detect TB in buffer, even in a diluted solution of many proteins. The proposed method offers high selectivity against mismatch sequences of TB, a good linear response range of 10 −18 moL L -1 to 10 -14 moL L -1 and a low minimum detection limit of 0.330 aM.