Polyethylene glycol mediated ZIF-8 encapsulation of catalase for enhanced catalytic activities

The limited recovery and high sensitivity of free enzymes to aggressive environments constrain their use in industrial processes. Metal-organic frameworks offer a promising protective matrix, with zeolitic imidazolate framework-8 (ZIF-8) widely studied as an enzyme immobilization carrier. However, enzyme deactivation frequently occurs due to the harsh synthetic conditions, which collectively compromise the structural integrity and catalytic activity of the biomacromolecule. In this paper, a one-pot synthesis strategy was employed to prepare polyethylene glycol (PEG)-mediated ZIF-8 immobilized catalase (CAT). Structural and morphological analyses using XRD, SEM, BET, and other techniques confirmed the successful encapsulation of CAT within the MOF matrix. The introduction of PEG as a surfactant significantly enhanced the stability and catalytic efficiency of CAT, resulting in an increased Michaelis constant (K M , 2.28 mM) and maximum reaction rate (V max , 33.81 μM/s). This study provides an effective approach to improve enzyme performance through MOF-based immobilization, offering valuable insights for advancing biocatalysis in industrial applications.