The construction of Fe-porphyrin nanozymes with peroxidase-like activity for colorimetric detection of glucose.

As a type of nanomaterials with enzyme-mimetic catalytic properties, nanozymes have attracted wide concern in biological detection. H 2 O 2 was the characteristic product of diverse biological reactions, and the quantitative analysis for H 2 O 2 was an important way to detect disease biomarkers, such as acetylcholine, cholesterol, uric acid and glucose. Therefore, there is of great significance for developing a simple and sensitive nanozyme to detect H 2 O 2 and disease biomarkers by combining with corresponding enzyme. In this work, Fe-TCPP MOFs were successfully prepared by the coordination between iron ions and porphyrin ligands (TCPP). In addition, the peroxidase (POD) activity of Fe-TCPP was proved, in detail, Fe-TCPP could catalyze H 2 O 2 to produce ·OH. Herein, glucose oxidase (GOx) was chosen as the model to build cascade reaction by combining Fe-TCPP to detect glucose. The results indicated glucose could be detected by this cascade system selectively and sensitively, and the limit of detection of glucose was achieved to 0.12 μM. Furthermore, a portable hydrogel (Fe-TCPP@GEL) was further established, which encapsulated Fe-TCPP MOFs, GOx and TMB in one system. This functional hydrogel could be applied for colorimetric detection of glucose by coupling with a smartphone easily. Nanozyme of Fe-TCPP and corresponding hydrogel were constructed, and they were further developed to detect glucose. [Display omitted] • A simple and efficient nanozyme for the detection of glucose is reported. • A universal hydrogel system containing both natural enzymes and nanozymes is developed. • Fe-TCPP@GEL could carry out the quantitative analysis of glucose by coupling with a smartphone easily. [ABSTRACT FROM AUTHOR]