Laccase–Polyacrylonitrile Nanofibrous Membrane: Highly Immobilized, Stable, Reusable, and Efficacious for 2,4,6-Trichlorophenol Removal

Abstract

Increasing attention has been given to nanobiocatalysis for commercial applications. In this study, laccase was immobilized on polyacrylonitrile (PAN) nanofibrous membranes through ethanol/HCl method of amidination reaction and successfully applied for removal of 2,4,6-trichlorophenol (TCP) from water. PAN membranes with fiber diameters from 200 nm to 300 nm were fabricated via electrospinning and provided a large surface area for enzyme immobilization and catalytic reactions. Images of scanning electron microscope demonstrated the enzyme molecules were aggregated on the nanofiber surface. The immobilized laccase exhibited 72% of the free enzyme activity and kept 60% of its initial activity after 10 operation cycles. Moreover, the storage stability of the immobilized laccase was considered excellent because they maintained more than 92% of the initial activity after 18 days of storage, whereas the free laccase retained only 20%. The laccase-PAN nanofibrous membranes exhibited high removal efficiency of TCP under the combined actions of biodegradation and adsorption. More than 85% of the TCP was removed under optimum conditions. Effects of various factors on TCP removal efficiency of the immobilized laccase were analyzed. Results suggest that laccase-PAN nanofibrous membranes can be used in removing TCP from aqueous sources and have potential for use in other commercial applications.

Enhancing catalytic performance of laccase via immobilization on chitosan/CeO 2 microspheres

“…The temperature profiles indicated an increase in the temperature for immobilized laccase activity compare to the free laccase activity. This result may be due to strengthening of the protein molecule's structural rigidity when it binds to the support, which reduces the molecular mobility [1]. In fact, the Schiff's reaction occurred between free aldehyde groups of glutaraldehyde (on the surface of the treated composite particles) and the side-chain amino groups of the laccase.…”

“…The effluents of industrial wastewater contaminated with dyes are harmful to the environment and human health [1,2]. Recently, enzyme-based treatments for the removal of reactive dyes have received much attention because they offer some advantages over physical and chemical processes, such as mild treatment condition, high efficiency of substrate removal, and the ability to handle large volumes of effluents [3,4].…”

Adsolubilization of 2,4,6-trichlorophenol from aqueous solution by surfactant intercalated ZnAl layered double hydroxides

“…Therefore, it is highly important to remove 2,4,6-TCP compound from aqueous solution. Currently, a number of methods have been developed to eliminate 2,4,6-TCP from wastewater [11][12][13][14][15]. However, these methods and materials usually involve high cost, complex process, and even may lead to secondary pollution during degradation process.…”

Laccase Immobilization by Chelated Metal Ion Coordination Chemistry

“…Polyacrylonitrile (PAN) nanofibers after surface modification have been studied and proved to be ideal support for laccase immobilization [17]. Amidoxime polyacrylonitrile (AOPAN) prepared by the chemical modification of the nitrile group was known as good adsorbent for metal ions [18].…”