Cu (II)-based metal-organic xerogels as a novel nanozyme for colorimetric detection of dopamine

Cu (II) based metal-organic xerogels (Cu-MOXs), which obtained by freeze-drying the metal-organic gels (Cu-MOGs), was simply synthesized under mild condition. Owe to the metal active sites in Cu-MOXs, the peroxidase substrate 3,3′,5,5′-tetramethylbenzidine (TMB) could be catalyzed by Cu-MOXs from TMB to the oxidation state of TMB (oxTMB) and the characteristic absorption peak intensity of oxTMB increased. Due to the inhibitory effect of dopamine (DA) on oxidation process of TMB, the characteristic absorption peak intensity of oxTMB decreased. Thus, the Cu-MOXs-TMB-H2O2 system was established and used for DA detection.104