Spectroscopic, biological activity, molecular docking and hydrogen storage studies of tetrazole-thione complexes

Six nano-tetrazole-thione complexes of the type [M(MmtzS)2] (MII = Ni (1); Zn(4); Cd (5) and Hg (6)} and [M2(MmtzS)4] (MII = Pd (2) and Pt (3)} were synthesized by treating by the reaction of one equivalent mole of inorganic salts {NiCl2 & sdot;6H2O; Na2PdCl4; K2PtCl4; ZnCl2; CdCl2 and HgCl2} with two equivalent moles of 1-methyl1,2,3,4-tetrazole-5-thiol (HMmtzS). The synthesized compounds were obtained through investigation by several physicochemical and spectroscopic techniques. XRD and SEM investigations indicate the crystalline and morphological structural studies of the complexes. Additionally, the MmtzSH ligand and their complexes were tested as antimicrobial agents against four pathogenic bacteria species (Escherichia coli, Klebsiella pneumonia, staphylococcus epidermidis, and Staphylococcus aureus), the results showed that the Ni(II) complex displayed the uppermost activity with the region inhibition within 19 mm(activity index = 72%) to 27 mm (activity index= 96 %) compared to the standard antibacterial drug and other complexes. The cytotoxic effect study was applied to colon carcinoma (CaCo2), and hepatoblastoma (HepG2) cell lines, using the MMT method for complexes (1-4). The Ni(II) complex has the highest activity among all tested compounds. In addition, the complexes 4-6 were chosen for hydrogen storage ability. The findings demonstrate the hydrogen-storing capacity of all tested complexes, with the zinc complex demonstrating the highest capacity at 40 bar and 173 K with 0.99 wt.%.