Covalent organic frameworks (COFs) have emerged as excellent candidates for enzyme immobilization due to their high surface tunability, diverse structures, inherent porosity, and metal-free characteristics. However, reports on optimizing the efficiency of immobilized enzymes in COFs by controlling linker length are scarce. In this work, horseradish peroxidase (HRP) and glucose oxidase (GOx), are co-immobilized on three imine-based COFs with different linker lengths using a one-pot method, resulting in HRP&GOX@COF (COF = LZU1, TbBD, TbDI). The immobilization of HRP and GOX using these three COF materials led to a slight decrease in enzyme activity compared to the free enzymes
however, a significant improvement in the stability of the immobilized enzymes was achieved. Besides, the experimental results demonstrate that all three materials HRP&GOX@COF (COF = LZU1, TbBD, TbDI) exhibit good colorimetric detection, stability, and recyclability for glucose and hydrogen peroxide (H