Bio‐MOFs based on natural phenolic, hematoxylin leverages biomedical applications: enzyme inhibition, antioxidant, and antibacterial properties

Here, using natural hematoxylin (HT) as linker, metal‐organic frameworks (MOFs) from Cu(II), Fe(II), and Fe(III) ions was prepared. The SEM images and DLS analyses revealed HT‐based MOFs are <micrometer sizes with the highest surface area value of 49.2 m2/g for HT‐Fe(III) MOFs. Interestingly, HT‐based MOFs exhibit fluorescent properties at λem=330 nm with fluorescence intensities of 11485, 2120, and 6790 (a.u) for HT‐Cu(II), Fe(II), and Fe(III) MOFs, respectively. Moreover, HT‐based MOFs inhibited α‐glucosidase enyzme in a concentration‐dependent manner e.g., 33.1%, 69.8%, and 59.7% of Cenzyme=500 mg/mL was inhibited by HT‐Cu(II)‐MOF, HT‐Fe(II)‐MOF, and HT‐Fe(III)‐MOFs, respectively. The minimum bactericidal concentration (MBC) values of HT‐Cu(II) MOFs for Escherichia coli (gram ‐), Staphylococcus aureus (gram +), and Candida albicans are determined as 5, 5, and 10 mg/mL, respectively. Also, the antioxidant activities of 250 ppm HT‐based MOF based on total phenol content (TPC) tests revealed 279, 208, 124, and 152 mg.gallic acid equivalent/mL (mg GA equivalency/mL) for HT, HT‐Cu(II) MOF, HT‐Fe(II) MOF, and HT‐Fe(III), respectively affirming that antioxidant properties were retained. Moreover, HT‐Fe(II) and HT‐Fe(III) MOFs (62.5 µg/mL) against human null‐1 lung cell line revealed cell viabilities of 98.7±12.2% and 88.9±11.7%, respectively as concentration‐dependent biocompatibility of MOFs.