▎ 摘　　要

New composite hydrogels were synthesized based on gum tragacanth (GT) carbohydrate and graphene oxide (GO). GT was sulfonic acid-functionalized and cross-linked by using 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and N,N'-methylenebisacrylamide (MBA) monomers and ceric ammonium nitrate (CAN) as an initiator. The prepared hydrogels were characterized by Fourier transform infrared spectrum (FT-IR), field emission scanning electron microscope (FE-SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). Adsorption process for removal of heavy metal ions has followed the pseudo-first-order kinetic model and fitted well with the Langmuir model. The maximum adsorption capacity (Q(m)) was 142.50,112.50 and 132.12 mg g(-1) for Pb(II), Cd(II), and Ag(I), respectively. The removal percentage decreased slightly after several adsorption/desorption cycles. The adsorbed Ag(l) ions in hydrogel were transformed to Ag-0 nanoparticles (with a narrow distribution and mean size of 13.0 nm) by using Achillea millefolium flower extract. The antibacterial performance of the Ag-0 nanocomposite hydrogel was also investigated. (C) 2016 Elsevier Ltd. All rights reserved.