Prolonged release of silver and iodine from ZIF-7 carrier with great antibacterial activity

Abstract

The study of substances with antibacterial properties has expanded greatly in recent years. However, there are few reports about the antibacterial activity of Ag@MOFs and I₂@MOFs. In this study, ZIF-7 was used to load iodine (I₂@ZIF-7) and silver nanoparticles (Ag@ZIF-7). FT-IR spectroscopy, PXRD, ZP, SEM, TEM, TGA, and BET analysis were used to investigate the successful synthesis of the samples. I₂@ZIF-7 and Ag@ZIF-7 showed prolonged release of I₂ and Ag⁺ up to 11 days, in addition to Zn²⁺ cation release. Finally, S. aureus and E. coli bacteria were used to study the antibacterial activity of the samples. The results showed that the antibacterial activity increased in the samples containing iodine (I₂@ZIF-7) and silver nanoparticles (Ag@ZIF-7). ZIF-7 has antibacterial components, zinc metal ions, as an antibacterial agent and a suitable ligand, along with iodine and silver, causing a synergistic effect, which was another reason for choosing ZIF-7. I₂@ZIF-7 and Ag@ZIF-7 showed a certain amount of antibacterial substance release such as iodine and silver gradually and for a long time (for about 11 days). I₂@ZIF-7 and Ag@ZIF-7 also showed better antibacterial activity than other reported Ag@MOFs and I₂@MOFs.