Synthesis, Characterization, Spectroscopic and Biological Studies of Zn(II), Mn(II) and Fe(II) Theophylline Complexes in Nanoscale

Three nanocomplexes of Zn(Ⅱ), Mn(Ⅱ), Fe(Ⅱ) with theophylline were synthesized by ultrasonic sonication method. Melting point, molar conductivity, solubility, flame atomic absorption, Fourier-transform infrared spectroscopy (FTIR), ultraviolet-visible (UV-vis) spectroscopy and C/H/N elemental analyses were used to investigate and suggest the structure of the nanocomplexes. Size and morphology of the nanocomplexes were measurement by transmission electron microscopy (TEM), ranging from 6-22 nm. Efficacy of the nanocomplexes synthesized was examined against four types of bacterial strains: Staphylococcus aureus, Bacillus subtilis (Gram-positive bacteria), Klebsiella pneumonia and Escherichia coli (Gram-negative bacteria). The results showed that all nanocomplexes had very high susceptibility to inhibit bacterial growth, as indicated by their inhibition zones between 98% and 100%.