2(3),9(10),16(17),23(24)-Octamethoxyphthalocyanine-Cu/CuFe2O4 nanocomposites with enhanced peroxidase-like activity for the sensitive colorimetric determination of glutathione

In this work, 2(3),9(10),16(17),23(24)-octamethoxyphthalocyanine (Pc(OH)8) was first used to modify Cu/CuFe2O4(Cu/CFO) nanospheres, and Pc(OH)8–Cu/CFO nanocomposites with enhanced peroxidase mimetic enzyme activity was obtained compared to the performance of Cu/CFO alone. SEM, XRD, and XPS were used to study the surface morphology, phase composition and elemental analysis of the newly synthesized Pc(OH)8–Cu/CFO. Using TMB as the chromogenic substrate, Pc(OH)8–Cu/CFO accelerate the oxidation process of chromogenic substrate 3,3′,5,5′- tetramethylbenzidine (TMB) by hydrogen peroxide in three minutes. The catalytic oxidation mechanism of Pc(OH)8–Cu/CFO on TMB was comprehensively investigated through free radical and fluorescence probe experiments. Based on the excellent catalytic performance of the composite materials, a simple and fast colorimetric sensing platform for the colorimetric detection of H2O2 and glutathione (GSH) was constructed in the range of 0.6–5 mM and 2–10 μM with detection limits (LODs) of 0.35 mM and 0.55 μM, respectively. In addition, using Pc(OH)8–Cu/CFO colorimetric detection for GSH has a lower detection limit, good selectivity and high sensitivity, which is expected to become an ideal material for GSH colorimetric detection.