The chemical modification of developed ethyl cellulose-based membrane was carried out to make it suitable for bioseparation. The different reagents were used for the modification of membrane to couple protein A (PA) to study the purification of immunoglobulin G (IgG) from blood. The chemical modification was carried out using relatively simple and mild reaction conditions. The attenuated total reflectance Fourier transform infrared analysis of chemically modified membrane showed new peak at 1,596.06 and 1,716.49 cm(-1). The scanning electron microscopy of PA-coupled membrane, which was used for IgG purification showed open pores and 950 +/- 21.5 LMH (L m(-2) h(-1)) operational flux at 0.5-bar out pressure. The flux of unmodified membrane was 1,746 +/- 18.5 LMH at 0.5-bar out pressure. The equilibrium adsorption concentration (318.5 +/- 5.9 mu g cm(-2)) was obtained at 3 h. The adsorption character of PA-coupled membrane was consistent with the Langmuir adsorption model and the non-specific binding was 67.08 +/- 1.3 mu g cm(-2). The sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis showed similar purification pattern for purified IgG from human serum and commercial preparation of IgG. All the results have suggested a high potential of PA-coupled ethyl cellulose-based membrane for large-scale purification of IgG.