Preparation and characterization of antibacterial thiosemicarbazide chitosan as efficient Cu(II) adsorbent.

In the present work a method has been developed for the preparation of thiosemicarbazide-chitosan (TSCS) exploring the evaluation of enhanced adsorption of metal ions and antibacterial activities via derivatization. The splitting of carbon-carbon (C-2 and C-3) bond of vicinal diols of the chitosan chain is planned in a way to figure a "Schiff base intermediate" which undergoes the addition reaction in order to enhance total nitrogen and sulphur content for the chelation of Cu(II) ions from aqueous solutions in a batch adsorption system. Fourier transform infrared spectroscopy (FT-IR), (1)H NMR, elemental analysis (CHN analyzer), X-ray diffraction (XRD) and differential scanning calorimetric (DSC) analyses were used for the characterization of the end product. Surface morphologies were also studied by scanning electron microscopy (FESEM). The adsorption results showed that maximum adsorption was achieved at a dose concentration of 1.5 g/L, temperature of 25 °C with contact time of 20 min. The adsorption properties of TSCS toward Cu(II) ions were evaluated and found to be 99 ± 1%. The antibacterial properties were evaluated against Escherichia coli bacteria confirming that the modified material (TSCS) possess enhanced antibacterial activities when compared with the virgin chitosan.