Thermal analyses data and antimicrobial screening of some new nano-structure five coordinated cadmium complexes

In this work, synthesis of some nano-structure five coordinated cadmium complexes of a new tridentate Schiff base ligand (L) under ultrasonic conditions is presented. The ligand and its cadmium complexes were characterized by various analyses such as FT-IR, UV–visible, 1H and 13C NMR spectra, XRD, SEM and TEM. According to applied techniques, the general formula of CdLX2 (X=Cl−, Br−, I−, SCN− and N3−) was suggested for the complexes. SEM, TEM and XRD analyses indicated that all complexes have nano-structure size in the range of 20–60nm. In the next step, ligand and its cadmium complexes were subjected for in vitro antibacterial activities against two Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Moreover in vitro antifungal properties of the compounds against Candida albicans and Aspergillus niger were investigated. The results indicated that all compounds show acceptable antibacterial and antifungal activities. Furthermore, the interaction of these complexes with DNA indicated that both ligand and its complexes can destruct the DNA structure. In final, thermal behaviors of all compounds were studied by TG/DTG/DTA analysis data. The thermo-diagrams showed that the compounds are decomposed via 2–3 temperature stages. Some thermo-kinetic activation data including Arrhenius constant, ΔE*, ΔH*, ΔS* and ΔG* of each thermal decomposition step were estimated graphically by use of experimental TGA data based on the Coats–Redfern equation.