Fe3O4 is a promising material for arsenic sequestration due to its specific affinity toward arsenic and feasible magnetic separation. How to further increase its adsorption capacity while maintain its lowfield separation is an interesting but challenging task. In this study nano-Fe3O4 was successfully coated onto the outer surface of polystyrene (PS) beads of 350-400 nm in diameter by the hetero-coacervation method, and the resulting composite PS-Fe3O4 was characterized using transmission electron microscope (TEM), X-ray powder diffraction (XRD), and electrophoresis measurement (EM). Its adsorption toward arsenate was investigated as a function of solution pH, arsenic concentration, contact time, and coexisting anions. The maximum adsorption capacity of PS-Fe3O4 was 139.3 mg/g Fe3O4, 77.7% greater than that of bulky Fe3O4. More attractively, it can be readily separated from water under a low magnetic field (<0.035 T). Continuous adsorption-desorption cyclic results demonstrated that arsenate-loaded PS-Fe3O4 can be effectively regenerated by NaOH solution, and the regenerated composite beads could be employed for repeated use without significant capacity loss, indicating that nano-Fe3O4 was steadily coated onto the surface of PS beads. Generally, PS beads could be employed as a promising host to fabricate efficient composites originated from Fe3O4 or other nanoparticles for environmental remediation. (C) 2012 Elsevier B.V. All rights reserved.