Biocompatible MOF-808 as an iodophor antimicrobial agent with controlled and sustained release of iodine

Abstract

In recent years, the increasing occurrence of microbial resistance to biocidal materials has become a serious problem. In contrast to other biocides, iodine seems to have no real resistance issue, but its instability causes pain and irritation. The metal–organic framework Zr₆O₄(OH)₄(BTC)₂(HCOO)₆ (MOF-808) is a highly thermally and chemically stable Zr-MOF synthesized from trimesic acid (H₃BTC). H₃BTC is a highly electron-deficient molecule that seems to make MOF-808 an appropriate adsorbent of non-polar iodine. Herein, activated MOF-808 was synthesized for caging the biocide, iodine. The obtained samples were characterized by FT-IR spectroscopy, PXRD, TGA, SEM, TEM, ZP and BET analyses. The adsorbed amount of iodine on the iodine-loaded MOF-808 (I₂@MOF-808) was estimated by thermogravimetric analyses (25.3%) and UV-vis spectroscopy (27.0%). Finally, its antibacterial activity was evaluated against S. aureus and E. coli with a reported 19 mm zone of inhibition for I₂@MOF-808 against S. aureus. Therefore, I₂@MOF-808 can be considered as a biocide that does not have the microbial resistance problem and also problems caused by the instability of iodine.