A novel biological approach on extracellular synthesis and characterization of semiconductor zinc sulfide nanoparticles

The expansion of reliable and eco-friendly process for synthesis of semiconductor nanoparticle is an important step in the emerging field of biomedical nanotechnology. In this communication, the zinc sulfide nanoparticles were biologically synthesized by using Serratia nematodiphila which was isolated from chemical company effluent. The surface plasmon resonance centered at 390 nm on the UV spectrum indicates the presence of zinc sulfide nanoparticles in the reaction mixture (S. nematodiphila and zinc sulfate); EDAX analysis also confirmed the presence of zinc sulfide nanoparticles. Scanning electron microscope image showed that the synthesized zinc sulfide nanoparticles were spherical in nature and nanoparticles of about 80 nm in size were obtained from transmission electron microscope images. The peaks in the XRD spectrum corresponding to (111), (220) and (311) show that the zinc sulfide nanoparticles are crystalline in nature. Fourier transforms infrared spectroscopy shows the functional groups of the nanoparticle in the range of 4,000-400 cm(-1). Further, the antibacterial activity of zinc sulfide nanoparticles was examined against Bacillus subtilis and Klebsiella planticola. The maximum zone of inhibition occurred at 200 mu l of silver nanoparticles. Due to potent antimicrobial and intrinsic properties of zinc sulfide, it is actively used for biomedical and food packaging applications.