Laccase-functionalized magnetic framework composite enabled chlorophenols degradation,a potential remediation for fungicides residues in leather

Chlorophenols,used as the fungicides in leather,are strictly limited in leather products.In this work,a metal-organic framework material,zeolitic metal azolate framework-7(MAF-7),was first used to encapsulate laccase(Lac)to prepare MAF-7/Lac bio-composites with 98.5%immobilization yield.Afterward,Lac/MNP@MOM was formed by introducing the magnetic nanoparticles(MNPs)into the Lac@MOM.MAF-7 with better hydrophilicity and stronger pH buffering ability,exhibits good compatibility with laccase,which can reserve the activity of laccase after immobilization.Moreover,the porous structure of MAF-7 is favorable for the sufficient contact between laccase and substrates.Lac/MNP@MOM exhibited excellent activity when exposed to high temperature,extreme pH,and organic solvents,which also simplified complex recovery steps.Furthermore,the degradation rate of 2,4-dichlorophenol(2,4-DCP)could reach as high as 97%within 24 h by immobilized laccase,and after nine consecutive cycles of operation,enzyme activity could remain over 80%,which gives it the potential for practical applications.