摘要
Recently,many efforts have been dedicated to creating enzyme-mimicking catalysts to replace natural enzymes in practical fields.Inspired by the pathological biomineralization behaviour of L-cystine,in this study,we constructed a laccase-like catalyst through the co-assembly of L-cystine with Cu ions.Structural analysis revealed that the formed catalytic Cu-cystine nanoleaves(Cu-Cys NLs)possess a Cu(I)-Cu(II)electron transfer system similar to that in natural laccase.Reaction kinetic studies demonstrated that the catalyst follows the typical Michaelis-Menten model.Compared with natural laccase,the Cu-Cys NLs exhibit superior stability during long-term incubation under extreme pH,high-temperature or high-salt conditions.Remarkably,the Cu-Cys NLs could be easily recovered and still maintained 76%of their activity after 8 cycles.Finally,this laccase mimic was employed to develop a colorimetric method for epinephrine detection,which achieved a wider linear range(9–455μmol·L^(−1))and lower limit of detection(2.7μmol·L^(−1)).The Cu-Cys NLs also displayed excellent specificity and sensitivity towards epinephrine in a test based on urine samples.
基金
This work was supported by the National Natural Science Foundation of China(Grant Nos.21621004 and 21676191).
