Preparation of Thermosensitive Polymer Immobilized Horseradish Peroxidase and its Application in Catalytic Degradation of Phenol

The immobilized horseradish peroxidase (P1-HRP) was prepared based on the affinity interaction between the phenylborate group in mVBA-b-p (AAm co AN) polymer (P1) and the adjacent dihydroxy group in horseradish peroxidase (HRP). The immobilization conditions of P1-HRP were optimized. Under the conditions of P1 concentration of 20 mg/mL, pH 8, temperature of 50 ℃, and immobilization time of 2 h, the HRP was immobilized to obtain the optimal immobilization amount (84.7 mg/g). The successful preparation of P1-HRP was demonstrated through characterizations such as laser scanning confocal microscopy (LCSM), scanning electron microscope (SEM), dynamic light scattering (DLS) and thermogravimetric analyzer (TGA). P1-HRP exhibited excellent pH stability, thermal stability and storage stability compared to the free horseradish peroxidase. P1-HRP had shown good application value in the degradation of phenol pollutants. After 10 repetitions of phenol degradation, the relative enzyme activity of P1-HRP could still be retained by 55.62%, indicating its good reusability. The optimal conditions for the catalytic degradation of phenol by P1-HRP were optimized. After catalytic degradation of phenol for 60 min under the same conditions, the degradation rate of P1-HRP (92.33%) was higher than that of free horseradish peroxidase (85.32%).