Amino acid-immobilized copper ion-modified carbon-based adsorbent for selective adsorption of bovine hemoglobin

Preparation of Ni-Mn ferrites magnetic nanoparticles through the ethanol solution combustion-calcination process for the adsorption of methyl blue

Ni-Mn ferrites magnetic nanoparticles (MNPs) were successfully prepared through the ethanol solution combustion-calcination process, and characterized by SEM, TEM, XRD, VSM, BET, and FTIR techniques. For smaller particle size and suitable magnetic property, the optimum element ratio of the material was Ni0.9Mn0.1Fe2O4, and the optimal preparation conditions were appropriate ethanol dosage to attain Fe3+ concentrations of approximately 0.85 M, calcination temperature of 400 °C, and calcination time of 2 h, their specific surface area was 136.5 m2/g, and their average particle size and saturation magnetization were 35 nm and 21.66 emu/g, respectively. The adsorption process of methyl blue (MB) onto Ni0.9Mn0.1Fe2O4 MNPs conformed to the pseudo-second-order adsorption kinetic model in the initial concentrations of 100-250 mg/L. In comparison with Langmuir and Freundlich adsorption isotherm models, the Temkin model (R2 = 0.9865) was observed to better demonstrate the state of MB onto Ni0.9Mn0.1Fe2O4 MNPs, revealing that the adsorption mechanism of MB onto Ni0.9Mn0.1Fe2O4 MNPs was the multi-molecular chemical process. The adsorption capacity of Ni0.9Mn0.1Fe2O4 MNPs for MB still maintained about 90% of the initial adsorbance after 6 times cyclic utilization of the nanoparticles by recalcination method, suggesting that Ni0.9Mn0.1Fe2O4 MNPs had excellent regeneration performance. In general, these results coupled with its environmental friendliness attributed the potential candidates for effluent remediation.

Cu(II)-Loaded Polydopamine-Coated Urchin-like Titanate Microspheres as a High-Performance IMAC Adsorbent for Hemoglobin Separation

Immobilized metal ion affinity chromatography (IMAC) adsorbents generally have excellent affinity for histidine-rich proteins. However, the leaching of metal ions from the adsorbent usually affects its adsorption performance, which greatly affects the reusable performance of the adsorbent, resulting in many limitations in practical applications. Herein, a novel IMAC adsorbent, i.e., Cu(II)-loaded polydopamine-coated urchin-like titanate microspheres (Cu-PDA-UTMS), was prepared via metal coordination to make Cu ions uniformly decorate polydopamine-coated titanate microspheres. The as-synthesized microspheres exhibit an urchin-like structure, providing more binding sites for hemoglobin. Cu-PDA-UTMS exhibit favorable selectivity for hemoglobin adsorption and have a desirable adsorption capacity towards hemoglobin up to 2704.6 mg g-1. Using 0.1% CTAB as eluent, the adsorbed hemoglobin was easily eluted with a recovery rate of 86.8%. In addition, Cu-PDA-UTMS shows good reusability up to six cycles. In the end, the adsorption properties by Cu-PDA-UTMS towards hemoglobin from human blood samples were analyzed by SDS-PAGE. The results showed that Cu-PDA-UTMS are a high-performance IMAC adsorbent for hemoglobin separation, which provides a new method for the effective separation and purification of hemoglobin from complex biological samples.