ZIF-67-derived Co3O4 hollow nanocage with efficient peroxidase mimicking characteristic for sensitive colorimetric biosensing of dopamine

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2021-02, Vol.246, p.119006, Article 119006
• Main Authors: Wang, Hongying, Fu, Wanying, Chen, Yanwei, Xue, Fengying, Shan, Guiye
• Format: Article
• Language: English
• Subjects: Co3O4; Dopamine; Nanoenzyme; Peroxidase; ZIF-67
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2020.119006

Co3O4 hollow nanocages (Co3O4 HNCs) were prepared by simple calcination with ZIF-67 as the precursor. Compared with ordinary nano-sized Co3O4, skeletal Co3O4 HNCs have a larger specific surface area and porosity, lead to better dispersion, which can expose more catalytic active sites, and obtain higher catalytic activity. Experiments indicate that Co3O4 HNCs are used as a catalyst to make H2O2 generate O2. At the same time, Co3O4 HNCs act as bridge to accelerate the electrons transfer from the chromogenic substrate 3,3′,5,5′-tetramethylbenzidine (TMB) to the dissolved oxygen and efficiently obtain blue oxidized TMB (oxTMB) at low concentration of H2O2. Steady-state kinetic analysis shows a lower Km and a higher Vmax value than other materials, indicating its excellent affinity and high catalytic efficiency. Based on the inhibitory effect of dopamine (DA) on TMB oxidation in the system, a sensitive, visual colorimetric biosensing method is developed. The calibration curve of DA has a good linear response at both high and low concentrations. Compared with other system, it has the unique advantage of very low detection limit, while retaining a wide detection range, and realizes the accurate detection of actual samples with different concentrations. [Display omitted] •Co3O4 hollow nanocages (Co3O4 HNCs) were derived from ZIF-67, with high specific surface area and high porosity.•Co3O4 HNCs possess higher peroxidase catalytic activity than other reported materials.•We successfully used Co3O4 HNCs for sensitive and rapid detection of dopamine concentration.•The system realized low detection limit and wide range detection of dopamine.