A comparison study about antibacterial activity of zeolitic imidazolate frameworks (ZIFs) prepared with various metal ions

Abstract

Herein, the synthesis of zeolitic imidazolate framework particles in water at room temperature using 2-methylimidazole (HmIm) as organic linker, and Co(II), Ni(II), Cu(II), Fe(II), Mg(II), Zn(II), Ce(III), La(III), Fe(III), and Ti(IV) ions is reported. The colors of the prepared ZIF particles varied depending on the metal ions used. The disappearance of NHring-N out of plane bending peak at 1845 cm−1 and weakening of the NH bending peak at 1597 cm−1 in the FT-IR spectrum of HmIm after ZIF synthesis confirmed successful preparation. Higher surface area values were observed for ZIF-Co(II) and ZIF-Zn(II) with values of 1423.4 and 1467.1 m2/g, respectively. The prepared ZIF-Fe(II) particles showed magnetic property. The antibacterial activities of ZIF particles also varied depending on metal ions. The highest antibacterial activities were observed for ZIF-Co(II) and ZIF-Cu(II) particles against P. aeruginosa (gram -, ATCC 10145), S. aureus (gram +, ATCC 6538), and C. albicans (fungi, ATCC 10231). The MIC values of ZIF-Co(II) particles were determined as 0.125, 0.25, and 1.0 mg/mL against P. aeruginosa, S. aureus, and C. albicans, whereas MBC values were determined as 0.25, 1.0, and 5.0 mg/mL, respectively. The inhibition zones for P. aeruginosa, S. aureus, and C. albicans in the presence of 10 mg ZIF-Cu(II) particles were measured as 22.7 ± 1.5, 24.3 ± 1.1, and 25.7 ± 0.6 mm, respectively.