A Co(II)–organic framework and peroxidase mimetic Hemin@metal–organic framework and its application in the colorimetric analysis of glucose

A Co(II)‐organic framework (Co‐MOF), [Co 3 (3,5‐bimpy) 2 (5‐cpia) 2 (H 2 O) 2 ], was constructed via the hydrothermal reaction of 3,5‐bis(1‐imidazoly)pyridine (3,5‐bimpy) and 5‐(2′‐carboxylphenoxy)isophthalic acid (5‐H 3 cpia). The Co‐MOF possessed a three‐dimensional (3D) porous architecture with the porosity of 22.4% per unit volume. The Co‐MOF@Hemin composite was further constructed via the encapsulation of Hemin into the Co‐MOF material. The constructed Co‐MOF@Hemin exhibited satisfactory peroxidase‐like activity through catalytic oxidation of the colorless peroxidase substrate 3,3,5,5‐tetramethylbenzidine (TMB) to a blue‐colored oxTMB in the presence of H 2 O 2 . Hence, the detection of H 2 O 2 was achieved with a wide linear range from 0.005 to 0.5 mM ( R 2 = 0.992) and a low detection limit of 1.26 μM. More importantly, the peroxidase‐like Co‐MOF@Hemin was suitable for the sensitive and selective detection of glucose under the presence of glucose oxidase (GOx), which reduced O 2 to H 2 O 2 . This analytical procedure for the detection of glucose had a linear range from 0.3 to 3 mM ( R 2 = 0.997), with a detection limit of 49 μM. The experimental results display the broad application prospects of the enzyme‐based MOFs in green and selective targets analyses.