Potential biomedical application of a new MOF based on a derived PET: synthesis and characterization

Metal-organic frameworks (MOFs) are materials with a large surface area and antimicrobial properties are advantageous properties for the controlled release of molecules for biomedical applications. However, their synthesis is expensive and harmful to the environment due to the use of organic ligands and solvents. Thus, this work proposes the synthesis of a new MOF by hydrothermal method using water as the solvent, aluminium nitrate as a metallic source, and bis(2-hydroxyethyl) terephthalate (BHET) as organic ligand, obtained via glycolysis of polyethylene terephthalate (PET); and its comparison with MIL53-Al MOF, synthesized from terephthalic acid (BDC) as organic ligand. Both MOFs were characterized by XRD, ATR-FTIR, N-2 physisorption, TGA, SEM and XPS; besides their in vitro biocompatibility was tested by porcine fibroblasts viability. The results indicate that aluminium ions are coordinated to both carbonyl and hydroxyl functional groups of the BDC and BHET organic ligands. The new BHET-Al MOF shows higher thermal stability than MIL53-Al, it also exhibits a macroporous structure in comparison with the microporosity of the MIL53-Al. BHET-Al MOF is not cytotoxic for porcine dermal fibroblasts growing on its surface for up to 48 h of culture, thus, this innovative MOF is a promising material for the controlled release of drugs.