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•A novel green synthesis method is employed for the synthesis of copper nanoparticles.•The average size of the synthesized Cu nanoparticles is in the range of 5–25 nm.•The obtained ...nanoparticles have shown good antibacterial activity against gram-positive and gram-negative bacteria.
In the present report, for the first time aqueous extract of Curcuma longa powder is used for the synthesis of Copper nanoparticles (Cu NPs) using a simple and cost effective method. Morphology, size, crystallinity, composition and microstructure of the synthesized Cu Nps are studied. Size of the particles are in the range of 5–20 nm. In addition to the above, antibacterial activity of the obtained Cu NPs is tested for both gram-positive and gram-negative microorganisms. Zone of inhibition of Cu NPs for gram positive bacteria is more compared to gram negative bacteria. The current work on green synthesis of metallic nanoparticles can be considered as an alternative method to avoid the usage of hazardous compounds and bitter reaction conditions in the production of metal nanoparticles. The obtained Cu NPs with their distinctive structural properties and effective biological effects can be used in applications viz. antimicrobial, antifungal, anticancer activity.
Bio-fabrication has become a safe approach for silver nanoparticles (Ag NPs). The plant-mediated biosynthesized Ag NPs have emerged as a potential substitute for conventional chemical formation. The ...biosynthesized Ag NPs were analyzed in terms of crystalline nature, morphology, chemical composition, particle size, stability, size, and shape of the particles. The XRD, FTIR, and TEM analysis indicate the presence of the bioactive secondary metabolites compounds. The bamboo-mediated Ag NPs demonstrated a notable antibacterial efficacy against Gram-positive and Gram-negative pathogenic microorganisms and showed significant antioxidant activity against DPPH free radicals. The degradation of methylene blue at various intervals under solar light irradiation was used to evaluate the photocatalytic performance of Ag NPs. Further, Ag NPs conveyed potent anticancer activity against MCF-7 cell lines with a significant value IC
50
. The bamboo leaves-mediated Ag NPs synthesized Ag NPs signified strong antibacterial, antioxidant, and anticancer activity; hence, it can be used in various biomedical applications and face mask coating to prevent the coronavirus after successful clinical trials in research laboratories.
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•Synthesized Ag and ZnO Nanoparticles via leaf extract of henna plant.•Acute oral toxicity and histopathology studies were done.•Showed non toxicity on tested mice for the period of ...14days.•Histopathlogical changes have been studied.
The Ag and ZnO nanoparticles are synthesized by a green method using Lawsonia inermis plant extract. The phytochemical constituent (2-hydroxy-1, 4-napthoquionone) found in the leaf extract of Lawsonia inermis plays an important role in the reduction and formation of Ag and ZnO nanoparticles. The biosynthesis of Ag and ZnO NPs was observed by the color change from colorless to dark brown and light brown. The FE SEM, TEM DLS analysis confirmed the average particle size of Ag and ZnO NPs as 100nm, 20nm, 28.5nm and 100nm, 20nm, 38.4nm respectively. Crystalline nature and presence of Ag and ZnO NPs were confirmed by XRD. The FT-IR spectra of the Ag and ZnO authorized the presence of phyto constituents as capping agent. From results of acute oral toxicity studies, it was found that Ag and ZnO NPs at 2000mg/kgb.w have shown no mortality during the treatment period. The present study revealed the safer use of eco-friendly green synthesized Ag and ZnO NPs in the field of nano-biomedicine.
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•Sm2O3 rice like nanorods was prepared by ESM-assisted hydrothermal method.•Sensitivity, stability and selectivity parameters analyzed for Sm2O3/rGO sensor towards LPG at RT.•The ...sensing mechanism explained based on Chemiresistive model.
Flexible electrochemical sensors have gained huge attention over their significant properties and the probability of applying to any wearable electronic devices. LPG traces in definite concentrations leads to a fire accident, adverse health effects, and even causes death. The current study focuses on a flexible, room temperature LPG sensor based on Sm2O3/rGO hybrid nanocomposite with different loading factors (1, 3, and 5 wt%) coated on flexible polyethylene terephthalate (PET) substrate working electrodes. Eggshell membrane (ESM) template constituents are acts as a reducing agent during the hydrothermal synthesis of Sm2O3 nanorods. Flexible Sm2O3/rGO hybrid Chemiresistive gas sensor was tested for various gas sensing parameters. The decoration of Sm2O3 nanorods on 3 wt% rGO sheets exhibited good selectivity to liquefied petroleum gas (LPG) at room temperature gives a response of 116% at 700 ppm of LPG with a short response, recovery time and gained 99% response after bending with 94.5% stability of the sensor.
At present tuneable properties and morphology of polymer composites have become fundamental forefront research interest in sensing applications. Using existing approaches with a new idea, this paper ...reports the synthesis of Polyaniline nanosheets (PANINS) with surface modification by nickel oxide nanoparticles (NiO) through in situ polymerization. The morphology and presence of functional groups of as obtained NiO-NPs @PANINS witnessed the formation of the thin surface of PANINS decorated by NiO-NPs using FESEM, TEM, and FTIR. The structural analysis of as prepared NiO-NPs and NiO-NPs@PANINS confirmed the crystallinity by insignificant stacking fault, dislocation density, and microstrain. Furthermore, the synthesized NiO and NiO@PANINS were used as a modified screen-printed electrode (SPE) for the fabrication of electrochemical non-enzymatic glucose sensor. The invented sensor used for amperometric non-enzymatic glucose sensor exhibited a high sensitivity of 5625 μA mM−1 cm−2, and low detection limit 0.06 μM. Besides that, the interference study shows excellent selectivity and also retains good stability. We believe that this NIO@PANINS nanocomposite could be utilized as low cost, an eco-friendly efficient electrode for the electrochemical biological sensor.
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•The NiO-NPs@PANINS was synthesized using SDS through in-situ polymerization method.•The NiO-NPs@PANINS/SPE used for non-enzymatic glucose sensing in 0.1 M NaOH. .•The NiO-NPs@PANINS/SPE showed a high sensitivity of 5625 μAmM−1cm−2 & LOD 0.06 μM.•NiO-NPs@PANINS/SPE was better for its selectivity, ease of synthesis and lowcost.
•A triboelectric nanogenerator based on ZnO nanosheets and PET was developed for the first time.•A cost-effective hot plate-assisted hydrothermal method was used for ZnO nanosheets preparation.•Open ...circuit voltage and power density of fabricated nanogenerator are ~4.9 V and 1 µW/cm2.•The fabricated TENG was employed to drive a digital watch and 24 LEDs with the help of a charged capacitor.
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The exploration of new triboelectric materials is considered a significant research area to reduce the cost and complexity of the triboelectric nanogenerator (TENG) device and improve its energy conversion efficiency. In this report, a new triboelectric material pair has been demonstrated to prepare an inexpensive and high-performance TENG. A low-cost hot plate-assisted hydrothermal process is used to prepare the ZnO nanosheets on an aluminum substrate. TENG is made using ZnO nanosheet film, PET/ITO, and operates in vertical contact separation mode. The proposed TENG generates electricity through contact electrification and electrostatic induction. The fabricated TENG is tested for the switching polarity test and confirmed the output voltage generated by TENG alone. The TENG can deliver an open-circuit voltage and short-circuit current of ~ 4.9 V and 10 µA, respectively, for repeated hand tapping.
Further, the performance of the proposed TENG is tested under resistive loads, and the maximum power density of 1 µW/cm2 observed at a load resistance of 5 MΩ. Similarly, TENG is also tested under capacitive loads and found the maximum energy stored value of 16.9 μJ at the load capacitance of 47 μF. In addition, the effect of different frequencies of the applied force and device size on the TENG response is studied. The TENG can light up 3 LEDs instantaneously and power the digital watch and 24 LEDs using an energy storage element. The present TENG shows a low-cost and straightforward process and can harvest energy from low-frequency bio-mechanical vibrations. The proposed TENG has potential applications in self-powered electronic devices and systems.
The present study emphasizes on designing a new series of isatin-dihydropyrimidinone derivatives by adopting a hybrid pharmacophore approach. Fe3O4 nanoparticles (Fe3O4 NP) are magnetically ...recoverable and are effective catalysts adequately used to synthesize Isatin-dihydropyrimidinones. Individual derivatives of Isatin and dihydropyrimidinone are equipotent to treat cytotoxicity.
The present work was planned to fuse two pharmacophores (Isatin, dihydropyrimidinone) and to examine any synergistic effect in the anticancer activity.
The individual compounds are synthesized by adopting appropriate synthetic routes like sandmayers and biginellis reaction and are fused together by using glacial acetic acid and Methanolic KOH to form novel Isatindihydropyrimidinone hybrids. All the new series of hybrids 7a-l were characterized by FT-IR, 1H NMR, 13C NMR, elemental analysis and Mass spectroscopy. The antioxidant activity of the synthesized compounds was assessed by using two models: 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) and Hydrogen peroxide (H2O2) scavenging assay.
From the results it can be inferred that nearly all the synthesized compounds have shown antioxidant activity at the tested dose as correlated with the standard ascorbic acid. The in vitro cytotoxic activity was assayed by using MTT assay. Compound 7l with IC50 values 22.13, 25.68 and 35.59 μM has significantly greater potency against MCF- 7, HeLa and IMR-32 cell lines.
The compounds with halogen and electron withdrawing groups at the C-5 position of isatin ring exhibited significant antioxidant and cytotoxic activity.
This study is about the influence of magnesium oxide (MgO) and zinc oxide (ZnO) nanoparticles on the morphology, structural, thermal and mechanical properties of the polylactic acid (PLA) films. The ...pure PLA and PLA nanocomposites were prepared using a cost-effective film applicator at 2 and 5 wt% of nanofillers. The dispersity and elements were examined by scanning electron microscopy with energy dispersive spectroscopy. For 2 wt% of nanofiller in the film, the agglomeration of nanoparticles was not observed, whereas for higher weight percentages agglomeration took place. X-ray diffraction study confirms the improved crystallinity of PLA at 2 wt% nanofillers. Thermal analysis of PLA composite films confirms that the values of glass transition (
T
g
), crystallization (
T
c
) and melting temperature (
T
m
) increased for 2 wt% and decreased for 5 wt% nanofillers. At 2 wt%, the glass transition temperatures of PLA/ZnO and PLA/MgO nanocomposite films are 63 and 62°C, respectively. Further, the tensile test confirms that 2 wt% of nanofiller-incorporated PLA films have better properties than 5 wt% of nanofiller due to the better dispersion of nanoparticles. At 2 wt% of MgO and ZnO nanoparticles, tensile strength (
T
s
) was increased to 19.4 ± 0.97 and 22 ± 1.1 MPa, respectively. The prepared PLA nanocomposite films with improved thermal and mechanical properties can be utilized in food packaging applications.
We report the efficient biogenic synthesis of silver nanoparticles (Ag NPs) using silver nitrate and extracts of different parts of
Theobroma cacao
: the husk (h-Ag NPs), pulp (p-Ag NPs), and seed ...(s-Ag NPs). In addition, we have tested the antibacterial and photocatalytic activities of the Ag-NPs. The Ag NPs obtained from husk, pulp, and seed extracts show variation in the particle size, dispersion, and morphology. UV–visible absorbance measurements reveal surface plasmon resonance bands at 425, 438, and 462 nm for the s-Ag, h-Ag, and p-Ag NPs, respectively. Transmission electron microscopy studies revealed the formation of monodisperse spherical Ag NPs with diameter ranging from 6 to 18 nm. Fourier transform infrared measurements of the as-synthesized Ag NPs indicate differences in the phytochemicals decorating the NP surfaces, which led to differences in the zeta potential, hydrodynamic radius, and polydispersity index. The p-Ag, h-Ag, and s-Ag NPs exhibited photocatalytic activity on exposure to sunlight from sun, achieving 35%, 29%, and 24% degradation of methylene blue (MB) within 60 min, respectively. Further, the p-Ag NPs showed 98.3% MB photodegradation after 180 min. The photocatalytic rate constants for the degradation of MB were also calculated. Finally, we found that the biogenic nanoparticles affect bacterial growth, possibly by causing protein leakage and cell death. The p-Ag NPs showed better antibacterial activity against
Bacillus subtilis
and
Escherichia coli
than h-Ag and s-Ag. The photocatalytic and antibacterial activities of the Ag NPs synthesized with
T. cacao
mainly depend on the particle size and the biomolecules on the surface of the NPs.
In this report, the antibacterial activity of pure polylactic acid (PLA), Zinc oxide (ZnO) incorporated PLA, and ZnO nanorods grown on the ZnO incorporated PLA films prepared by a simple film casting ...method was studied. ZnO nanorods were grown on ZnO mixed PLA films by a simple hydrothermal method at 80 °C temperature. The SEM study confirms the formation of ZnO nanorods on PLA. The length and diameter of nanorods are approximately 2–3 µm and 500 nm, respectively. The high elemental percentage of Zn and O was observed in the energy-dispersive spectra of ZnO nanorods grown ZnO mixed PLA film due to the presence of ZnO nanorods on the surface of the film. The TGA analysis has shown thermal stability enhancement by approximately 10 °C in the ZnO nanorods grown film compared to pure PLA film. Furthermore, the antibacterial activity of these films was tested against
Escherichia coli
(
E
.
coli
) bacteria and
Staphylococcus aureus
(
S
.
aureus
) bacteria. The zone of inhibition values for pure PLA, ZnO incorporated PLA, and ZnO nanorods grown films are 0, 16, 19 mm and 0, 18, 21 mm for
E. coli
and
S. aureus,
respectively. More antibacterial activity was observed for the film containing ZnO nanorods on its surface than the pure PLA and ZnO mixed PLA films. This process of growing ZnO nanorods on PLA film surfaces can be easily adapted to large-scale production for packaging applications.
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