Facile and green preparation of multifeatured montmorillonite-supported Fe3O4-Cu2+ hybrid magnetic nanomaterials for the selective adsorption of a high-abundance protein from complex biological matrices

Magnetic montmorillonite (MMT) nanomaterials are developing into highly promising adsorbents because they possess a large surface area, and excellent magnetism. However, the lack of a green synthesis and the absence of appropriate functional groups for selective adsorption limit their application on a wider scale. In this work, magnetic MMT nanocomposites (Fe3O4-Cu2+/MMT) were prepared in a facile manner without employing any hazardous organic solvents. A qualitative comparison of several factors showed these reported materials are synthesized via a procedure that is more green than is traditionally reported for these types of adsorbents. These Fe3O4-Cu2+/MMT nanomaterials function as a novel, selective adsorbent for the bovine hemoglobin (BHb). The MMT and Fe3O4-COOH nanoparticles respectively act as the carrier and magnetic component, while the copper ions play the role of a co-functional monomer for selectively removing BHb. In addition to imparting magnetic properties onto the material, the Fe3O4-COOH nanoparticles also facilitate the attachment of copper ions through chelation during the synthesis. The chemical, physical, and adsorptive properties of Fe3O4-Cu2+/MMT nanomaterials were comprehensively investigated via adsorption experiments and various characterization methods. The results demonstrated that the hybrid nanomaterials exhibited multiple outstanding features such as their excellent magnetism, adsorption capacity (638.6 mg g(-1)), and selectivity (S > 3.69) towards BHb. Moreover, the nanocomposites have been effectively utilized for selectively separating and enriching BHb molecules from bovine blood samples, confirming its practicality for analysis of real biological samples.

Automated summary

This work presents a highly promising adsorbent, magnetic montmorillonite (MMT) nanomaterials, which possess large surface area and excellent magnetism. A facile and green synthesis method is developed for preparing magnetic MMT nanocomposites (Fe3O4-Cu2+/MMT) without using hazardous solvents. The nanocomposites exhibit excellent magnetism, high adsorption capacity, and selectivity towards bovine hemoglobin, making them practical for analysis of real biological samples.