Magnesium oxide (MgO) nanostructures were prepared using microwave-assisted (M 1) and hydrothermal (M 2) methods and characterized by XRD, SEM and FT-IR. It exhibits cubic structure with an average ...crystallite size of 20 nm (M 1) and 14 nm (M 2) and the lattice strain (WH plot) is 0.0017 (M 1), 0.0037 (M 2). It's spherical and rods like structures are confirmed through SEM and TEM. The vibrational stretching mode of MgO is 439 (M 1) and 449 cm−1 (M 2). The optical bandgap is estimated as 5.93 eV (M 1) and 5.85 eV (M 2) through UV–Vis spectra. The fluorescence spectrum shows emission peaks at 414 and 437 (M 1) and 367 and 385 nm (M 2). The photodegradation studies of MgO nanostructures were assessed by monitoring the decolorization of methylene blue and Congo red dyes in aqueous solution under sunlight irradiation. The antibacterial activities of M 1 and M 2 are investigated against the gram-negative (Escherichia coli, Shigella flexneri, Salmonella typhi, Proteus mirabilis, Aeromonas hydrophila and Vibrio cholera) and gram-positive (Bacillus subtilis and Rhodococcus rhodochrous) bacteria. The zone of inhibition of 24 (M 1) and 25 mm (M 2) indicates high antibacterial activity towards the gram negative bacterium A. hydrophila. Confocal laser scanning microscopic (CLSM) analysis was utilized for understanding the variation in antibacterial activity between different orientations of MgO nanostructures. The cytotoxicity assay confirmed that the prepared nanostructures are non – toxic to normal healthy RBC's. In-vitro anticancer efficiency (IC50) of MgO nanostructures against human lung cancer cell line (A549) was investigated.
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•MgO nanostructures were prepared by the hydrothermal and microwave-assisted method.•MgO was studied against organic pollutants such as Methylene blue and Congo red dyes by photocatalytic activity.•It exhibits good antibacterial activity (foodborne pathogens) and also studied hemolytic activity.•It is used as an efficient anticancer therapeutic agent against human lung cancer cell line (A549).
A facile approach for the preparation of CdO–NiO–ZnO mixed metal oxide nanocomposite was demonstrated by microwave assisted method and characterized by XRD, SEM with EDS and FTIR. XRD exhibits CdO ...(cubic), NiO (cubic), ZnO (hexagonal) structure with an average crystallite size of 37, 23 and 20 nm respectively. The lattice strain and the dislocation density are evaluated by W–H method. SEM and TEM images reveal the morphology as sheet like structure and FTIR indicates the characteristic stretching frequency as Cd–O (687 cm
−1
), Ni–O (865 cm
−1
) and Zn–O (472 cm
−1
). From the UV–Vis spectra, the bandgap is estimated as 2.75 eV. The fluorescence spectrum shows the emission of blue–violet (455 nm), green (524 nm) and red (678 nm). The prepared nanocomposite acts as an excellent photocatalyst for the removal of methylene blue dye under sun light irradiation. Furthermore, the antibacterial activity for concentrations (25, 50, 75 and 100 µg/mL) was carried out in-vitro against gram negative (G − Ve) i.e.
Escherichia coli, Pseudomonas aeruginosa, proteus mirablis, Aeromonas hydrophila, Salmonella typhi
and
Vibrio cholerae
; gram positive bacteria (G + Ve):
Staphylococcus aureus, Rhodococcus rhodochrous and Bacillus subtilis
. Confocal laser scanning microscopy confirms the rupture of the bacterial cell wall.
In this study, CdO, NiO, and CdO-NiO nanocomposites (NCs) were synthesized and investigated by X-ray diffraction (XRD), scanning electron microscopy, and Fourier transform-infrared spectroscopy. XRD ...detected cubic structures with average crystallite sizes of 45 nm for CdO, 25 nm for NiO, and 30 nm for CdO-NiO. The band gap was estimated based on the ultraviolet–visible spectra. The near band edge emission was determined according to the luminescence spectrum. The antibacterial activities were tested against seven foodborne pathogens and the zones of inhibition with the Gram-negative bacterium Bacillus subtilis measured as 30 mm with CdO, 20 mm NiO, and 27 mm with CdO-NiO. The death of the bacterial cells was confirmed by confocal laser scanning microscope analysis. Cytotoxicity assays indicated the non-toxic effects of the NCs on normal healthy red blood cells. Furthermore, the in vitro cytotoxic effects of the CdO, NiO, and CdO-NiO NCs were examined using the human MCF-7 breast cancer cell line based on 3-4,5-dimethylthiazol-2-yl2,5-diphenyltetrazolium bromide assays with normal mouse embryonic fibroblasts (NH3T3) under identical conditions.
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•Microwave-assisted synthesis of CdO, NiO, and CdO-NiO nanocomposites (NCs).•Luminescence spectra showed CdO-NiO NCs are suitable for biological applications.•CdO-NiO NCs had antibacterial and anticancer activities.
Nanostructures of noble metals were immensely studied owing to their eminent salient features like morphology, controllable size dispersity and surface chemistry. Herein, we report a facile and ...eco-friendly route to synthesize gold nanoparticles (CGAuNPs) within a shorter period of time using the aqueous fruit extract of Couroupita guianensis Aubl. (CGFE) as a potential bioreductant to reduce Au3+ ions into their nanoscale counterparts. Growth of CGAuNPs generates a shift in the color of reaction medium due to the excitation of surface plasmon resonance (SPR) which produces an intense absorbance peak at 530nm in UV–Visible spectroscopy. Fourier transform infrared spectroscopy (FTIR) confirms the active role of water soluble phenolic compounds in achieving the reduction and stabilization of CGAuNPs. Additionally, transmission electron microscope (TEM) and X-ray diffraction (XRD) studies revealed that the synthesized CGAuNPs were anisotropic face centered cubic crystalline in nature, having an average size of 26±11nm. Dynamic light scattering (DLS) and Energy dispersive spectroscopic (EDAX) results were proved that the synthesized CGAuNPs were free from contaminants and they were stable, possessing negative electric charge without aggregation. On the other hand, in vitro antioxidant assays demonstrate that the aqueous CGFE and formulated CGAuNPs possess extraordinary antioxidant properties. Hemocompatibility assay depicts the safe nature of synthesized CGAuNPs for biomedical applications. Thus, the results of present study will be useful to synthesize AuNPs instantly via green chemistry route for its valuable applications in nanomedicine.
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•Instant green synthesis of anisotropic gold nanoparticles using fruit extract of C. guianensis•Physio-chemical characterization and identifying the role of phenolic antioxidants on functionalization of NPs•In vitro antioxidant and biocompatibility assessment of synthesized NPs
CdO nanoparticles (NPs) were synthesized (hydrothermal) with cadmium acetate and ammonium hydroxide as starting materials and characterized by XRD, FE-SEM and FTIR. It exhibits face centred cubic ...structure with an average crystallite size of 43 nm and the lattice strain (W–H plot) is 0.0029. The surface morphological image appears particle like structure (150 nm). The vibrational stretching mode of Cd–O is 620 cm
−1
whereas micro Raman reveals the overtone at 389 cm
−1
. The optical energy bandgap is found to be 2.47 eV from the UV–Vis spectra. Five emission peaks were recorded at 360, 429, 488, 527 and 640 nm upon excited at 290 nm. The SHG efficiency is 0.84 times of KDP. The photocatalytic performance has been evaluated of the CdO NPs for the degradation of methylene blue under sunlight irradiation. CdO NPs were screened for their in vitro antibacterial activity against human pathogens such as Gram negative (
Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris
) and Gram positive (
Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis
) bacteria has been investigated.
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•CdO–ZnO nanocomposite was prepared by microwave-assisted method.•Nanocomposite was characterized with UV–Vis, FTIR, SEM, XRD and EDS.•CdO–ZnO nanocomposite has excellent antibiotics ...for biomedical applications.
CdO–ZnO nanocomposite was prepared by microwave-assisted method and characterized by X-ray crystallography (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FT-IR). It exhibits hexagonal cubic structure with an average crystallite size of 27nm. From the UV–Vis spectra, the bandgap is estimated as 2.92eV. The fluorescence spectrum shows a near band edge emission at 422nm. In addition the antibacterial activity of CdO–ZnO nanocomposite was carried out in-vitro against two kinds of bacteria: gram negative bacteria (G −ve) i.e. Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and gram positive bacteria (G +ve): Staphylococcus aureus, Proteus vulgaris and Bacillus spp. This study indicates the zone of inhibition of 40mm has high antibacterial activity towards the gram positive bacterium S. aureus.
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•MgO nanorods have been synthesized from Andrographis Paniculata leaf extract.•It shows a good antibacterial activity against aquatic and food borne pathogens.•It shows a good ...anticancer activity against human breast cancer cell line (MCF-7).
MgO has been synthesized using Andrographis paniculata (A. paniculata) which crystallizes in the cubic structure with the average crystallite size of 35nm. SEM reveals the formation nanorods (diameter: 46nm, length: 185nm). From the luminescence spectrum, oxygen defects (467nm) were observed. It shows good antibacterial activity with a zone of inhibition of 19mm (V. cholerae) and 29mm (S. flexneri) against aquatic and foodborne pathogens. It also exhibits anti-breast cancer (human breast adenocarcinoma MCF-7: IC50:15.76µg/mL) activity along with biocompatibility.
CdO nanoparticles based on
Andrographis paniculata
plant extract were synthesizedby biological method and characterized by XRD, FESEM, HRTEM and FTIR. XRD exhibits face centred cubic structure with ...an average crystallite size of 22 nm and the lattice strain (W–H plot) is 0.0023. From the HRTEM, the particles are spherical. The vibrational stretching mode of Cd–O is 456 cm
−1
. From the UV–Vis spectra, the optical energy bandgap is estimated as 2.33 eV. The photoluminescence emission peaks at 360, 430, 486, 528 and 616 nm are observed for the excitation at 220 nm. The electrochemical study by cyclic voltammetry reveals the quasi reversible reduction and irreversible oxidation versus Saturated Calomel Electrode (SCE). The potential is referred to the F
c
/F
c
+
couple under the experimental conditions. The biosynthesized CdO nanoparticles are tested against gram positive (
Rhodococcus rhodochrous
and
Staphylococcus aureus
) and gram negative (
Escherichia coli, Aeromonas hydrophila
and
Vibrio Cholera
) bacterial strains. It is noted that the bioengineered CdO nanoparticles show a good antibacterial activity (zone of inhibition:
E. coli
-16 mm) bacteria.
In the present study, a sustainable green chemistry approach was established to fabricate magnetic Fe
3
O
4
nanoparticles (Fe
3
O
4
NPs) using the aqueous fruit extract of edible C. guianensis ...(CGFE). Synthesized NPs were further confirmed with different high-throughput characterization techniques such as UV-visible spectroscopy, FT-IR, XPS, DLS and zeta potential analysis. Additionally, XRD, AFM, HRTEM and SQUID VSM demonstrate the generation of crystalline CGFe
3
O
4
NPs with mean diameter of 17 ± 10 nm. Interestingly, CGFe
3
O
4
NPs exhibit a stupendous bactericidal action against different human pathogens which depicts its antimicrobial value. A significant dose-dependent cytotoxic effect of CGFe
3
O
4
NPs was noticed against treated human hepatocellular carcinoma cells (HepG2).
Calcium hydroxide nanoparticles (Ca(OH)
2
NPs) were formulated through microwave assisted route and characterized by XRD, FTIR and FESEM. It exhibits hexagonal crystal structure with an average ...crystallite size of 30 nm. The TEM images show the agglomerated nanoparticles. From the UV–Vis spectra, the bandgap is estimated as 5.5 eV. A broad emission band with maximum intensity at around 430 nm is observed in photoluminescence (PL) spectrum of Ca(OH)
2
NPs at room temperature. The dielectric constant and loss were studied as a function of frequency at room temperature (Ɛ
r
= 25.0 and Ɛ
′′
= 3.94 at 10 kHz).The relative powder second harmonic generation efficiency (SHG) of Ca(OH)
2
NPs is comparable with the standard KDP. Antibacterial activity of Ca(OH)
2
NPs at concentrations 15 and 30 µg/mL were screened against gram negative (
Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa, Shigella flexneri, Proteus vulgaris, Klebsiella pneumoniae
and
Proteus mirabilis
) and gram positive (
Bacillus subtilis, Micrococcus luteus, and Streptococcus aureus
) bacteria by measuring the inhibition zone.
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