Facile green synthesis, analysis, in vitro antidiabetic and antimicrobial activity of ZnO macropores.

Rapid increase in population and development in industry causes many problems such as microbial contaminations and chronic diseases such as diabetes. Materials synthesized at nanoscale are novel antidiabetic and antimicrobial agents. ZnO nanoparticles with macropores characteristics are synthesized by green methods. Turmeric, clove buds and green tea extracts are used as additives. X-ray diffraction results confirmed the hexagonal wurtzite structure of ZnO nanoparticles and crystallinity was quit high in case of green tea extract. Sample synthesized with clove shows relatively higher crystallite size (10.64) which is pertaining to variation in Zn2+ and OH- ions. The nanoparticles are more or less spherical in nature, macropores and clustered together revealed by SEM images. Macroporosity of the sample was further confirmed by nitrogen adsorption-desorption isotherm. The deep absorption band at 605 cm-1 in FTIR spectra attributed the wurtzite-type ZnO. The major dominating sharp peak was detected at 437 cm-1 in Raman spectra which is a feature of the wurtzite hexagonal phase ZnO. UV-Vis spectra showed red shift from wavelength 362 to 375 nm with different plant extracts. Impedance analysis showed a high dielectric constant and low tangent loss in case of green tea extract. ZnO synthesized using green tea exhibited ~ 95% α-glucosidase inhibition activity and 91% α-amylase inhibition activity. Antibacterial results revealed that synthesized ZnO nanoparticles showed activity against Bacillus subtilis and E. coli with inhibition zone 35 mm and 29 mm, respectively.

Optical, Dielectric, Magnetic, Photocatalytic, and Antibacterial Properties of Ga-Doped BiGaxFe1-xO3 Synthesized by the Microemulsion Approach.

The effect of Ga-substitution on bismuth ferrite BiGaxFe1-xO3 (x = 0, 0.05, 0.10, 0.15, 0.20, and 0.25) properties was investigated, which was fabricated using a microemulsion route. X-ray diffraction analysis confirmed that specimens had a single-phase rhombohedral structure with space group R3̅c. The concentration of Ga had an impact on various properties such as structural parameters, crystalline size, porosity, and unit cell volume. The samples exhibited notable values for the dielectric constant, tangent loss, and dielectric loss in the low-frequency range, which declined as the frequency increased due to different polarizations. The increment in the AC conductivity was associated with rise in frequency. The P-E loops demonstrated that the samples became more resistive as the Ga concentration increased. The retentivity (Mr) and saturation magnetization (Ms) values reduced as the Ga content increased, although all samples had Hc values within the range for electromagnetic materials. The Ga-substitution had a synergistic effect on the electrochemical characteristics of BiGaxFe1-xO3, resulting in greater conductivity than that of undoped BiFeO3. These enhanced properties contributed to their higher photocatalytic activity in the degradation of crystal violet under visible light irradiation. The doped BiGaxFe1-xO3 exhibited 79% dye degradation after 90 min of illumination compared to 54% for pure BiFeO3. Recycling experiments confirmed the stability and reusability of the synthesized nanoparticles. The antibacterial activity of the samples was certified against various microbes, and the doped BiGaxFe1-xO3 showed promising activity. Thus, doped materials are good candidates for memories, dielectric resonators, and photovoltaics because of their high dielectric constant and AC conductivity, while their higher photocatalytic activity under visible light makes them promising photocatalysts for removing noxious and harmful effluents from wastewaters.

NiO/MnFe2O4 Nanocomposite Photoluminescence, Structural, Morphological, Magnetic, and Optical Properties: Photocatalytic Removal of Cresol Red under Visible Light Irradiation.

In this study, pure nickel oxide (NiO), manganese ferrite (MnFe2O4 or MFO), and binary nickel oxide/manganese ferrite (NiO/MFO1-4) nanocomposites (NCs) were synthesized using the Sol-Gel method. A comprehensive investigation into their photoluminescence, structural, morphological, magnetic, optical, and photocatalytic properties was conducted. Raman analysis, UV-Vis spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction techniques were used to characterize the materials. The synthesized samples exhibited superparamagnetic behavior, as revealed by our analysis of their magnetic properties. A lower recombination rate was shown by the photoluminescence analysis, which is helpful for raising photocatalytic activity. The photocatalytic activity was evaluated for the degradation of Cresol Red (CR) dye. 91.6% of CR dye was degraded by NiO/MFO-4 nanocomposite, and the NC dosage as well as solution pH affected the photocatalytic performance significantly. In four sequential photocatalytic cycles, the magnetically separable NCs were stable and recyclable. The enhanced photocatalytic activity and magnetic separability revealed the potential application of NiO/MFO-4 as an efficient photocatalyst for the removal of dyes from industrial wastewater under solar light irradiation.

Optical, Photocatalytic, Electrochemical, Magnetic, Dielectric, and Ferroelectric Properties of Cd- and Er-Doped BiFeO3 Prepared via a Facile Microemulsion Route.

A series of Cd- and Er-doped bismuth ferrites were synthesized using a simple microemulsion technique. The influence of Cd and Er doping on the structural, ferroelectric, photocatalytic, and dielectric properties of bismuth ferrite (BFO) was examined in this research. The prepared materials were examined by X-ray diffraction, Raman, scanning electron microscopy, and UV-vis techniques. The XRD patterns reflected the formation of a monophasic rhombohedral structure with the space group R3-c and an average crystallite size calculated to be in the range of 29 to 32 nm. The saturation polarization (Ps), coercivity (Hc), and retentivity (Pr) of the materials were investigated by a hysteresis loop (P-E), and it was perceived that increasing the dopant contents improved the Ps and Pr values, which may be due to the variation of metal cation valence states. In accordance with the photoluminescence (PL) spectra, a highly substituted material displayed lower recombination and increased charge separation rate (e--h+), which eventually contributed to a higher photocatalytic degradation performance of the prepared NMs. Furthermore, as the frequency and dopant concentration increased, the dielectric loss decreased, which could be due to different types of polarization. Bi1 - xCdxFe1 - yEryO3 showed well-saturated hysteresis loops (P-E) with enhanced saturation polarization near 9.7 × 10-4 µC·cm-2. The remnant polarization of the BFO and BFOCE NPs was 2.26 × 10-4 and 8.11 × 10-4 µC·cm-2, respectively, under a maximum electric field, which may be due to the variation of the metal cation valence states. The improved ferroelectric and dielectric properties of Bi1 - xCdxFe1 - yEryO3 NPs are attributed to the reduced concentration of defects, the different domain behavior, and the valence state of Cd and Er ions. The electrochemical (crystal violet (CV) and I-V) properties of Bi1 - xCdxFe1 - yEryO3 were all influenced by the dopant concentrations (Cd and Er). The synergistic effects of Cd and Er on the substituted material enhanced the specific capacitance in comparison to undoped BiFeO3. The photocatalytic activity to degrade CV under visible irradiation increased in BFOCE as the dopant (x,y) concentration increased from 0 to 0.25 by showing 84% dye degradation in comparison to pristine BiFeO3 (53% only) within 120 min under visible light. Moreover, the stability of these prepared nanoparticles was confirmed using recycling experiments, with the results indicating that the synthesized nanomaterials demonstrated promising stability and reusability.

Spectroscopic investigation of phase transformation of calcium oxalate dehydrates (renal calculi) using acidic Bryophyllum pinnatom powder.

Urolithiasis is one of most common renal disorders, characterized by the formation of kidney stones (renal calculi) through the crystallization process within the urinary system. The frequently observed renal calculi are calcium oxalate renal calculi and treatment is done by shock wave method or lithotripsy which is harmful for other cells of the internal system. The objective of this work was to evaluate in vitro diagnosis of calcium oxalate kidney stones in the aqueous solution of Bryophyllum pinnatum. The B. pinnatum powder was mixed in apple cider vinegar and lemon juice separately to make solution 1 and 2 respectively. Apple cider vinegar and lemon juice were used as solvents due to their acidic and body compatible nature. Two surgically removed stones was dipped in solution 1 and 2. After two weeks, kidney stone of weight 2.7 g is completely dissolved in solution 2 while a considerable weight reduction of other kidney stone has been observed in solution 1. Fourier transform infrared (FTIR) spectroscopy results show the presence of two strong absorption peaks at 610 and 912 (cm-1) in both solutions after dissolution of urinary stones are related to calcium oxalate dehydrate (COD). Raman spectra further confirm the dissolution of COD in solution having Raman shifts at 504 and 910 (cm-1). Cluster formation and aggregation of particles has been observed in scanning electron microscopy images. This in vitro study proves that a mixture of Bryophyllum pinnatum powder and lemon juice is a best remedy to remove kidney stones.

Biodegradation of gelatin stabilized tetragonal zirconia synthesized by microwave assisted sol-gel method.

The purpose of current work of is to organize stabilized tetragonal zirconia (t-ZrO2) nano-particles with microwave abetted sol-gel technique. To increase the stability and shrink the crystal size, both microwave (MW) and gelatin components are used as structure guiding methods. Gelatin was used with the aim of bone implantations, as raw materials used in gelatin production are cattle bones. It contains purified collagen protein (a main protein that in the extracellular matrix found in the body's various connective tissues) that also helps in implantations and repairing. Moreover, MW heating provides a uniform heating and control of microstructures. Zirconium oxychloride was used as precursor of zirconium Effect of gelatin contents (1g, 2g, 3g, 4g and 5g) was observed. X-ray diffraction (XRD) analysis attributes the presence of phase pure t-ZrO2 at low gelatin content 3g with crystallite size ∼6.68296 nm. Formation of phase pure t-ZrO2 without post heat treatment is due to sufficient amount of gelatin to coat the zirconia crystals. Relatively higher x-ray density has been observed in case of phase pure t-ZrO2 at 5g of gelatin content. Value of the hardness is increasing from 1263 to 1443 HV with gelatin content due to phase strengthening. Raman shift presents characteristic peak at 148 cm-1 of tetragonal zirconia. Phase fraction calculated from Raman spectra is in good agreement with XRD data. At 3g of gelatin content porous structure has been observed in scanning electron microscope images. This porosity decreases with gelatin content and the distribution of particles is more uniform, and dispersion is better. The porosity of the samples decreases and reaching a minimum value at 5g of gelatin content, at which the sample was the densest. The size of nanoparticles is in the range of 500-600 nm. Optimized t-ZrO2 is soaked in stimulated body fluid (SBF) for 1, 2, 4, 8, 12, 18 and 24 weeks. Slight variation in weight and hardness has been observed even after 24 weeks of soaking.

The electrochemical, dielectric, and ferroelectric properties of Gd and Fe doped LaNiO3 with an efficient solar-light driven catalytic activity to oxidize malachite green dye.

This work investigates the effects of double ion substitution on the ferroelectric, electrochemical, dielectric and photocatalytic properties of Gd and Fe doped La1-yGdyNi1-xFexO3 nanoparticles (NPs). La1-yGdyNi1-xFexO3 was fabricated by facile micro-emulsion path and its properties were studied by thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman scattering, Fourier Transform of Infrared (FTIR), energy dispersive x-rays (EDX) techniques. It has a distorted rhombohedral shape with crystallite size within the range of 17-23 nm. The doped material has a spherical heterogeneous morphology, and its surface area increased with increased doping. The electrochemical (CV, EIS, and I-V), conductivity and dielectric (dielectric constant and low dielectric & tangent loss) properties of La1-yGdyNi1-xFexO3 were dependent on the contents of the dopants (Gd and Fe). The doped material had improved specific capacitance compared to the undoped LaNiO3 due to the synergistic effect of Gd and Fe on the doped materials. The conductivity of Gd and Fe doped LaNiO3 5.16 × 104 Sm-1 was enhanced compared to the undoped LaNiO3 3.52 × 10-2 Sm1. Furthermore, hysteresis loop was used to investigate the coercivity (Hc), saturation magnetization (Ms) and remanence (Mr) of the material. The Ms and Mr values were enhanced with the content of the dopants. The photocatalytic activity (PCA) of the material in degrading malachite green (MG) dye was studied. La1-yGdyNi1-xFexO3 NPs was able to degrade up to 96.4% of the dye under visible light irradiation in 50 min. La1-yGdyNi1-xFexO3 has remarkable dielectric, electrochemical, ferroelectric and photo-catalytic properties and have potential applications in microwave, electrical, electronic, energy storage devices. It is also an active photo-catalyst material for the removal/oxidation of toxic pollutants from the environment.

Incorporation of engineered nanoparticles of biochar and fly ash against bacterial leaf spot of pepper.

In agriculture, the search for higher net profit is the main challenge in the economy of the producers and nano biochar attracts increasing interest in recent years due to its unique environmental behavior and increasing the productivity of plants by inducing resistance against phytopathogens. The effect of rice straw biochar and fly ash nanoparticles (RSBNPs and FNPs, respectively) in combination with compost soil on bacterial leaf spot of pepper caused by Xanthomonas campestris pv. vesicatoria was investigated both in vitro and in vivo. The application of nanoparticles as soil amendment significantly improved the chili pepper plant growth. However, RSBNPs were more effective in enhancing the above and belowground plant biomass production. Moreover, both RSBNPs and FNPs, significantly reduced (30.5 and 22.5%, respectively), while RSBNPs had shown in vitro growth inhibition of X. campestris pv. vesicatoria by more than 50%. The X-ray diffractometry of RSBNPs and FNPs highlighted the unique composition of nano forms which possibly contributed in enhancing the plant defence against invading X. campestris pv. vesicatoria. Based on our findings, it is suggested that biochar and fly ash nanoparticles can be used for reclaiming the problem soil and enhance crop productivity depending upon the nature of the soil and the pathosystem under investigation.

Nickel nanoparticle synthesis using Camellia Sinensis as reducing and capping agent: Growth mechanism and photo-catalytic activity evaluation.

Recently, the biosynthesis of nanoparticle attracted the attention of scientific community due to its simplicity, ease and eco-friendly nature. In the present study, Camellia Sinensis (C. Sinensis) leaves extract was employed for the synthesis of nickel nanoparticles (NiNPs). The fabricated NiNPs were characterized by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) and X-ray diffraction techniques. The photocatalytic activity (PCA) was evaluated by degrading crystal violet (CV) dye. The NiNPs size was in the range of 43.87-48.76nm, spherical in shape and uniformly distributed with magnetization saturation of 0.073 emu/g. The NiNPs showed promising PCA under solar light irradiation. At optimized conditions, up to 99.5% CV dye degradation was achieved. Results revealed that biosynthesis can be adopted for the synthesis of NiNPs in nano-size range since it is simple, cost effective and eco-friendly in nature versus physico-chemical methods.