Magnetic composite microsphere immobilized laccase and preparation method thereof

Abstract

The invention relates to a magnetic composite microsphere immobilized laccase and a preparation method thereof, and belongs to the field of environmental microbiology. In the immobilized laccase, metal-chelated magnetic composite microspheres are taken as a carrier, and laccase is immobilized on the carrier through coordination bonding action. The preparation method comprises two steps of: preparing the carrier, namely synthesizing magnetic ferroferric oxide nanoparticles by using a chemical precipitation process, preparing core-shell magnetic silica by taking the nanoparticles as cores through a sol-gel method, grafting polymer containing carbonyl or amino on the surface of the magnetic silica by taking gamma-chloropropyltrimethoxysilane as a medium, and preparing a functional carrier capable of immobilizing the laccase by chelating transition metal ions (such as Cu2+. Zn2+, Ni2+ or Co2+); and immobilizing the laccase, namely performing coordination adsorption of the laccase on the surface of the carrier, washing, and drying to obtain the finished product of immobilized laccase. The immobilized laccase prepared by the method has high stability and activity and quick magnetic response, is easily recovered from a reaction system and can be repeatedly used; and the preparation process is simple and the cost is low.

Description

technical field [0001] The invention relates to a magnetic composite microsphere immobilized laccase and a preparation method of the immobilized laccase. More specifically, it is to prepare a magnetic composite microsphere immobilized laccase capable of rapid magnetic separation and good operational stability. Background technique [0002] Laccase is a copper-containing polyphenol oxidase that exists widely in various organisms. Laccase can catalyze oxygen in the air to directly oxidize and decompose various phenolic dyes, substituted phenols, chlorophenols, thiophenols, bisphenol A, aromatic amines, etc. In the presence of laccase mediators (ABTS, HBT, etc.), laccase It can also catalyze the degradation of diphenylmethane, N-substituted p-phenylenediamine, organophosphorus compounds (pesticides) and dioxins related to lignin. Due to its wide substrate specificity and good stability, laccase has important application value in paper industry, wastewater treatment, biologica...

AI Technical Summary

Problems solved by technology

Among them, the cross-linking method and the covalent bond method have relatively severe reaction conditions, and the loss of enzyme activity is relatively large; the encapsulation method has a large loss of enzyme activity because the substrate binding site and active center are blocked by the carrier; the adsorption method has mild conditions, The active part of the enzyme and its spatial conformation are not easy to be destroyed, but the enzyme immobilized by ionic bonds, hydrogen bonds, dipole bonds and hydrophobic bonds in the adsorption method is easily affected by the pH and ionic strength of the reaction medium and falls off from the carrier.