One-step preparation of hydrophilic metal-organic framework materials with bimetallic linkers and polycarboxylic acid ligands and their adsorption properties

The bimetallic metal-organic frameworks (MOFs) with free carboxyl groups and bimetallic centers (expressed as MIL-53(Fe, Al)-COOH) are successfully synthesized by a simple one-step method. The preparation conditions and adsorption properties of the materials are studied. The introduction of trimellitic acid effectively enhances the hydrophilicity of the resultant MOFs and the obtained MIL-53(Fe, Al)-COOH shows better adsorption performance than corresponding monoligand and monometallic center MOFs. The results show hydrogen bond interaction between free carboxyl groups of MOFs and amino and carboxyl groups of glutathione(GSH) is the predominant driving force for GSH adsorption. The enrichment results demonstrate that the prepared MIL-53 (Fe, Al) -COOH has the ability to enrich GSH from aqueous solution up to 221.46 mg g−1, which indicates that MIL-53 (Fe, Al)-COOH could be used as a promising potential adsorbent to enrich GSH from aqueous solution.