Affinity membranes were prepared with poly(vinylidene fluoride) (PVDF) hollow fibers or flat membranes as the matrix, 1,6-hexanediamine (HDA) as the space arm, and amino acid-L-phenylalanine (L-Phe), L-tryptophane (L-Trp) and L-histidine (L-His) as the hydrophobic ligands, respectively. X-ray photoelectron spectroscopy (XPS) analysis results indicated that the contents of oxygen and nitrogen increased from 5.6% to 16.5% and 0.6% to 3.0% on the membrane surface after L-Phe modification, respectively, while fluoride content decreased from 38.3% to 23.0%. The effects of operation parameters such as pH value and ionic strength, on the human gamma-globulin (HGG) adsorption capacity of the affinity membranes were investigated in a batch system. The adsorption phenomena appeared to follow a typical Langmuir adsorption isotherm under the optimal condition, where the maximum adsorption capacity (q(m)) Of L-Phe affinity membrane for gamma-globulin was 0.318 mg/cm(2) membrane and the equilibrium constant (K-d) value was found to be 0.453 mg/mL solution from the Scatchard plot. Forty hollow fibers with a membrane area of 0.0188 m(2) in the membrane module adsorb 21 mg HGG from 10 mL human plasma with a purity of 83.9% in a single-pass mode. And the affinity membrane represented good stability throughout repeated adsorption-elution cycles. (c) 2006 Published by Elsevier B.V.