Surface engineerings of polyacrylonitrile-based asymmetric membranes towards biomedical applications: An overview

Polyacrylonitrile (PAN) membranes have attracted much attention due to a variety of excellent characteristics, which include thermal stability nd tolerance to most solvents, atmosphere, bacteria and photo irradiation. Therefore, their exploitation also covers many fields, like pervaporation, ater treatment, enzyme immobilization, and hemodialysis. However, the relative poor hydrophilicity and biocompatibility get the membranes usceptible to protein adsorption and cell adhesion that may cause biofouling and immunoreactions, especially when the membranes are used in lood-related systems. This review presents various surface engineerings for PAN-based membranes, which mainly refers to grafting polymerization also known as “grafting-from” method), partially hydrolysis, macromolecule immobilization (also known as “grafting-to” method), and enzyme mmobilization. To render the membrane surface with biocompatibility for hemodialysis, the concept of mimicking the outer surface of cells is ritical. For example, biomacromolecules such as chitosan, heparin or insulin can be tethered on the PAN-based membranes to improve their surface emocompatibility remarkably. In addition, one of the potential applications of PAN-based membranes is as enzyme immobilization supports. Over 5 relative literatures are listed and briefly discussed with different enzymes, modified supports, and coupling methods. However, the application rial for these enzyme-immobilized membranes is still elementary. 2007 Published by Elsevier B.V.