A novel method is described for facile fabrication of immobilized Cu2+ chelated cellulose/magnetic hydroxyapatite hybrid beads (denoted as Cu2+ Cell/MHAP) by an emulsification technique. In this process, the particles of MHAP, as the main component of the adsorbent, were prepared by simply mixing iron oxide with N-(phosphonomethyl)-iminodiacetic acid (PM-IDA) and followed by hydroxyapatite (HAP) deposition in aqueous solution. The obtained MHAP particles were suspended in cellulose solution and emulsified into Cell/MHAP hybrid beads. Finally, chelating Cu2+ on Cell/MHAP through oxygen ions of PO4 3– groups gave the immobilized metal affinity adsorbent. The combination of immobilized Cu2+ ligands, MHAP particles, and magnetic response together with the large size of the spherical cellulose support endowed the adsorbent with excellent adsorption selectivity, high adsorption capacity, and easy recovery of adsorbent from solvent, respectively. By physical characterization, Cu2+ Cell/MHAP possessed a large specific surface area of 94.2 m2 g–1 and a uniform spherical shape in size of about 137.4 ± 19.5 μm. The adsorption evaluation indicated that Cell/MHAP has a high static adsorption capacity (4533.1 mg g–1) of bovine hemoglobin. Obviously, high adsorption capacity is ascribed to small size and good dispersion of Cu2+ chelated HAP particles in spherical cellulose supports, which provided sufficient specific surface area and suitable volume for protein adsorption. The practical separation potential of Cell/MHAP was evaluated by using diluted bovine blood as a probe, and high adsorption selectivity was confirmed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis. Together with superparamagnetism, large size, and excellent adsorption performance, the adsorbent of Cell/MHAP has great potential in the field of histidine-rich protein purification.

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Cellulose beads consist of natural polysaccharide fibers and are widely used in various industrial materials and applications. Nevertheless, the key challenge is how to effectively avoid the tedious preparation process and environmentally harmful chemicals that exist in traditional fabrication routes. This study proposes a green and facile route to fabricate porous cellulose beads by selecting bamboo fibers as raw material. Without a tedious multistep process (dissolution, emulsification, and regeneration) and environmentally harmful solvents, porous cellulose beads were formed directly on bamboo fibers under aqueous phase with sodium periodate. Varied methods of SEM, XRD were applied to characterize porous cellulose beads at different fabrication stages. By this investigation, the feasible mechanism toward spherical cellulose formation was raised. After being modified with glycine, the cellulose beads were evaluated by means of adsorption isotherm and kinetics for investigating their adsorption potential by using Co 2+ and Cu 2+ as probes. All of the results illustrated that the porous cellulose beads by this strategy showed excellent adsorption efficiency for the removal of metal ions from wastewater.

This work reports the synthesis of a magnetic weak anionic spherical adsorbent with large size and starlike structure by magnetic induced self-assembly of organic latexes followed by modification with diethylaminoethyl hydrochloride (DEAE-HCl). The prepared adsorbent features unique starlike long chains stacked by anisotropic latexes (1 μm), large particle size (250 μm), and magnetic response. According to N 2 adsorption−desorption analysis, the starlike adsorbent possesses both specific surface area of 55.2 m 2 g −1 and total mesopore volume of about 2.7 cm 3 g −1 . After being modified with DEAE, the weak anionic adsorbent is evaluated for its adsorption performance. The analysis proves that the adsorbent approaches not only high static adsorption capacity of 113.05 mg mL −1 for BSA adsorption but also fast adsorption rate for approaching the adsorption equilibrium within less than 40 min. Additionally, the large particle size and magnetic response of the adsorbent facilitate the easy recovery of adsorbent from aqueous solution by simple filtration and/or external magnetic force. Hence, the prepared magnetic starlike spherical adsorbent is expected to have potential application in highperformance and large-scale purification of proteins.

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