Synthesis of Biogenic Copper Nanoparticles Embedded in Graphene Oxide-Chitosan Composite and Its Anti-Bacterial and Cytotoxic Activities.

In the current scenario, nanoparticle synthesis has been fascinated by biogenic approaches than the chemical methods. However, reproducibility of the source stands essentially in nanoparticle synthesis. Nanoparticle synthesis by fungi has more advantages such as the potential for bioaccumulation, immunity towards toxicity, relatively easier to handle, simpler in synthesis and downstream processing. In this study, biogenic copper nanoparticles (CuNPs) were embedded within graphene oxide-chitosan (GO-CS) polymer to endure the biocompatibility and toxicological effects on both normal and cancer cells. The characteristics of the copper nanoparticles/graphene oxide-chitosan (CuNPs/GO-CS) nanocomposites was found to be superior to the GO-CS. This is evident from the results obtained from X-ray diffraction technique, UV-visible spectroscopy, atomic force microscope, fourier transform infrared spectroscopy, fluorescence spectroscopy, confocal laser scanning microscope and scanning electron microscopy. The synthesized new copper nanoparticles/graphene oxide-chitosan (CuNPs/GO-CS) nanocomposites were studied for their anti-bacterial activity against Escherichia coli MTCC 443 and anti-cancer activity on breast cancer MCF7 cell lines.

Synthesis, spectral characterization and DNA bindings of tridentate N2O donor Schiff base metal(II) complexes.

To evaluate the biological preference of synthetic small drugs towards DNA target, new metal based chemotherapeutic agents of Cu(II), Co(II), Ni(II) and Zn(II), 2,4-diiodo-6-((pyridin-2-ylmethylimino)methyl)phenol (L) Schiff base complexes (1, 2, 3 &4) having N,N,O donor system respectively were synthesized and thoroughly characterized. The IR results confirmed the tridentate binding of the ligand with metal centre during complexation and reflects the proposed structure. The density function theory calculations were also used to further investigate the electronic structure and properties of ligand and complexes. The preliminary investigation of herring Sperm (HS-DNA) interaction propensity of complexes 1-4 were carried out in Tris-HCl buffer at pH 7.1 to demonstrate their mode of interactions. The obtained results reveal that these complexes significantly interact with DNA on the grooves, further, this observed mode of interactions was also confirmed by molecular docking evaluations. The complexes 1-4 were also screened for antimicrobial evaluations which demonstrated that their significant activity against various human pathogens. The cleavage studies with pBR322 plasmid DNA revealed higher nuclease activity of 1 as compared to other complexes.