biosorption of diclofenac by magnetic biosorbent (m-ecoli)

Diclofenac sodium (dcf), 2-[(2,6-dichlorophenyl)amino] benzene acetic acid, monosodium salt is widely used as a non-steroidal anti-inflammatory drug with high consumption. it therefore presents a serious risk to both human health and the environment and is among the pharmaceuticals that are most commonly found in aqueous effluents. in this study, a novel magnetic biosorbent (m-ecoli) was successfully prepared by immobilizing escherichia coli (e.coli) on nano-sized magnetic iron oxides, and its efficacy in dcf biosorption was investigated. to determine the characterization of the synthesized m-ecoli biosorbents, vibrational sample magnetometry (vsm), scanning electron microscope (sem), energy dispersive x-ray (edx) spectroscopy fourier transform infrared (ft-ir) spectroscopy analyses were performed and the effects of contact time, temperature, biosorbent dose and initial dcf concentration on the biosorption process were investigated. isothermal, kinetic, and thermodynamic calculations were performed to determine which mechanism is consistent with biosorption. it was found that the dcf biosorption on m-ecoli corresponded to the langmuir isotherm and the biosorption kinetics corresponded to the pseudo-second-order kinetic model. the thermodynamic analyses indicate that the biosorption of dcf on the m-ecoli nano-sorbent is physical. the maximum biosorption capacity was found to be 46.01±0.12 mg/g.