Bioinspired hierarchical CoAl-LDH/MFe2O4(Ni, Zn, Co) as peroxidase mimics for colorimetric detection of glucose

Novel hierarchically porous CoAl-LDH (layered double hydroxides)/MFe2O4(Ni, Zn, Co) hybrids with excellent peroxidase-like catalytic activity, high selectivity and reusability were first fabricated by using natural cotton as a bio-template. Among them, CoAl-LDH/NiFe2O4 exhibited the best intrinsic peroxidase-like property due to its 3D hierarchically porous structure with more exposed active sites, which could effectively catalyze peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2 to produce typical blue color reaction. A facile and visual system for glucose detection using glucose oxidase was successfully established, which exhibited a sensitive response to glucose in the range of 25-400 mu M with detection limit of 13 mu M based on the hydroxyl radical originated from the decomposition of H2O2 by the catalysis of CoAl-LDH/MFe2O4(Ni, Co, Zn) hybrids. This work offered an effective strategy to achieve morphology-controllable hierarchically porous materials and provided a new insight into seeking novel enzyme mimetics with enhanced catalytic activities.