A series of new Schiff bases of 4-(methylthio)benzaldehyde derivatives 3(a-i) were synthesized by the reaction of 4-(methylthio)benzaldehyde with various amines 2(a-i). Newly synthesized compounds were characterized by elemental analyses, UV-visible, FT-IR, Mass and 1H NMR spectral studies. All compounds were evaluated for their in vitro antibacterial activity against clinically isolated strains i.e., E. Coli, P. Fluorescence, M. Luteus and B. Subtilis. These compounds were screened for their antioxidant activity by 2,2-diphenyl-1-picryl-hydrazyl (DPPH•) and ferrous ion chelating assay (Fe2+) methods. The cytotoxicity assay was performed by tryphan blue dye exclusion method. Compounds 3g, 3h and 3i exhibited good antibacterial activity when compared with other compounds in the series against tested pathogenic bacterial strains. All the compounds showed antioxidant activity, where compound 3b was the best radical scavenger and Fe2+ ion scavenger. These findings showed that the Schiff bases of 4-(methylthio)benzaldehyde derivatives possess antioxidant activity with different mechanism of actions towards the different free radicals tested. Among these derivatives, 3b and 3h had the strongest activity against human peripheral lymphocytes.
A new durable antibacterial cotton fabric was successfully prepared by free-radical graft copolymerization of acrylic acid (AA) and itaconic acid (IA) onto a cotton fabric in an aqueous medium. Ammonium persulfate (APS) was used as the initiator in the presence of a crosslinker, methylene bisacrylamide (MBA). The nanocomposite hydrogel was obtained from in situ formation of silver nanoparticles from reduction of silver cations by sodium borohydride. A proposed mechanism for nanocomposite formation was suggested and the effect of ratio of IA to AA on water absorbency discussed. FTIR, UV-Vis, X-ray, and scanning electron microscopy were employed to characterize the structure of the prepared superabsorbent. The antibacterial activity of the hydrogel was tested qualitatively and quantitatively. Results showed that the silver nanoparticle-loaded fabric has potent antibacterial activity to Escherichia coli Gram-negative bacteria.