Biosynthesis of Co3O4 nanomedicine by using Mollugo oppositifolia L. aqueous leaf extract and its antimicrobial, mosquito larvicidal activities.

Nanotechnology is a relatively revolutionary area that generates day-to-day advancement. It makes a significant impact on our daily life. For example, in parasitology, catalysis and cosmetics, nanoparticles possess distinctive possessions that make it possible for them in a broad range of areas. We utilized Mollugo oppositifolia L. aqueous leaf extract assisted chemical reduction method to synthesize Co3O4 nanoparticles. Biosynthesized Co3O4 Nps were confirmed via UV-Vis spectroscopy, scanning electron microscope, X-ray diffraction, EDX, Fourier-transform infrared, and HR-TEM analysis. The crystallite size from XRD studies revealed around 22.7 nm. The biosynthesized Co3O4 nanoparticle was further assessed for mosquito larvicidal activity against south-urban mosquito larvae Culex quinquefasciatus, and antimicrobial activities. The synthesized Co3O4 particle (2) displayed significant larvicidal activity towards mosquito larvae Culex quinquefasciatus with the LD50 value of 34.96 µg/mL than aqueous plant extract (1) and control Permethrin with the LD50 value of 82.41 and 72.44 µg/mL. When compared to the standard antibacterial treatment, Ciprofloxacin, the Co3O4 nanoparticle (2) produced demonstrates significantly enhanced antibacterial action against the pathogens E. coli and B. cereus. The MIC for Co3O4 nanoparticles 2 against C. albicans was under 1 µg/mL, which was much lower than the MIC for the control drug, clotrimale, which was 2 µg per milliliter. Co3O4 nanoparticles 2, with a MIC of 2 µg/mL, has much higher antifungal activity than clotrimale, whose MIC is 4 µg/mL, against M. audouinii.

Studies on the interaction of mononuclear metal(II) complexes of amino­naphthoquinone with bio-macromolecules.

Three metal(II) complexes [CoLCl2], [CuLCl2] and [ZnL2Cl2] {L = 2­chloro­3­((3­dimethylamino)propylamino)naphthalene­1,4­dione} have been synthesized and characterized using analytical, thermal and spectral techniques (FT-IR, UV-Vis, ESR and ESI-MS). The structure of the L has been confirmed by single crystal XRD study. The complexes show good binding propensity to bovine serum albumin (BSA) having relatively higher binding constant values (104 M-1) than the ligand. Fluorescence spectral studies indicate that [CoLCl2] binds relatively stronger with CT DNA through intercalative mode, exhibiting higher binding constant (2.22 × 105 M-1). Agarose gel electrophoresis run on plasmid DNA (pUC18) prove that all the complexes showed efficient DNA cleavage via hydroxyl radical mechanism. The complexes were identified as potent anticancer agents against two human cancer cell lines (MCF7 and A549) by comparing with cisplatin. Co(II) complex demonstrated greater cytotoxicity against MCF7 and A549 cells with IC50 values at 19 and 22 µM, respectively.

Metal complexes of naphthoquinone based ligand: synthesis, characterization, protein binding, DNA binding/cleavage and cytotoxicity studies.

Protein binding, DNA binding/cleavage and in vitro cytotoxicity studies of 2-((3-(dimethylamino)propyl)amino)naphthalene-1,4-dione (L) and its four coordinated M(II) complexes [M(II) = Co(II), Cu(II), Ni(II) and Zn(II)] have been investigated using various spectral techniques. The structure of the ligand was confirmed by spectral and single crystal XRD studies. The geometry of the complexes has been established using analytical and spectral investigations. These complexes show good binding tendency to bovine serum albumin (BSA) exhibiting high binding constant values (105 M-1) when compared to free ligand. Fluorescence titration studies reveal that these compounds bind strongly with CT-DNA through intercalative mode (Kapp 105 M-1) and follow the order: Cu(II) > Zn(II) > Ni(II) > Co(II) > L. Molecular docking study substantiate the strength and mode of binding of these compounds with DNA. All the complexes efficiently cleaved pUC18-DNA via hydroxyl radical mechanism and the Cu(II) complex degraded the DNA completely by converting supercoiled form to linear form. The complexes demonstrate a comparable in vitro cytotoxic activity against two human cancer cell lines (MCF-7 and A-549), which is comparable with that of cisplatin. AO/EB and DAPI staining studies suggest apoptotic mode of cell death, in these cancer cells, with the compounds under investigation.

Synthesis, characterization and DNA binding/cleavage, protein binding and cytotoxicity studies of Co(II), Ni(II), Cu(II) and Zn(II) complexes of aminonaphthoquinone.

The Co(II), Ni(II), Cu(II) and Zn(II) complexes of an aminonaphthoquinone ligand (L) have been prepared and characterized using analytical and spectral techniques. The structures of L and its Zn(II) complex are confirmed by single crystal X-ray diffraction study. The results indicate that Co(II), Ni(II) and Zn(II) complexes possess tetrahedral geometry while Cu(II) complex exhibits square planar structure. The interaction of L and its complexes with CT-DNA reveal that they could interact with CT-DNA through intercalation. The DNA cleavage studies of the L and its complexes indicate that the Cu(II) and Ni(II) complexes cleave the circular form of the DNA relatively to a greater extent than the other complexes. The results of the interaction of these compounds with bovine serum albumin (BSA) indicate that the complexes exhibit a strong binding to BSA over the L. The in vitro anticancer activities indicate that these compounds exhibit substantial activity against human breast (MCF7) and lung cancer (A549) cell lines. The characteristics of apoptosis in cell morphology have been observed using AO/EB and DAPI staining and the results suggest that an apoptotic mode of cell death with these compounds. The overall results and discussion indicate that coordination of metal ions with the ligand enhances the biological activity.