A new and convenient approach for surface immobilization of heparin onto PE porous membranes is reported.3

4-dihydroxy-L-phenylalanine (L-DOPA)

a catecholic amino acid

is an important component of mussel adhesive proteins (MAPs).Based on the strong adhesive behavior of poly(DOPA) on solid surface

hydrophobic PE porous membranes was surfacemodified by self-polymerization of L-DOPA in aqueous solution.Subsequently

heparin was immobilized covalently onto PE/poly(DOPA) composite membranes by the coupling between heparin and poly(DOPA) layer.The immobilization of poly(DOPA) and heparin was confirmed by X-ray photoelectron spectroscopy (XPS).The results of water contact angle measurements showed that the hydrophilicity of PE membranes was significantly improved by the introduction of poly(DOPA) and heparin.The effects of poly(DOPA) and heparin on membrane surface morphologies were also investigated by scanning electron microscopy (SEM).Despite the decreased pore amount and pore size on membrane surface after-poly(DOPA) and heparin immobilization

the improved hydrophilicity would be beneficial to promote permeability and biocompability of PE membranes.