Effect of calcination temperature induced structural modifications on the photocatalytic efficacy of Fe2O3-ZrO2 nanostructures: mechanochemical synthesis.

Water contamination due to organic pollutants is a challenging issue around the globe, and several attempts have been made to deal with this issue. Out of which, the semiconductor-based photocatalytic process had gained much attention and proved to be an efficient, easy, and economical process for the removal of organic dyes from aqueous solutions. For this purpose, the iron oxide-zirconium dioxide nanocomposite (Fe2O3-ZrO2 NC) was prepared via a simple mechanochemical process using a mortar and pestle, followed by a calcination process at 300, 600, and 900 °C. Different physicochemical analyses were carried out in order to investigate the successful synthesis of Fe2O3-ZrO2 NC and the effect of temperature on the crystallinity, surface area, pore size, phase composition, sample morphology, and particle/crystallite size. The Fe2O3-ZrO2 NCs were subjected to a photocatalytic test under solar light irradiation against fluorescein dye in an aqueous medium, and the photocatalytic performance was examined under the influence of calcination temperatures, pH, catalyst dose, and initial concentration. The stability of the Fe2O3-ZrO2 NCs was also checked by recycling them for five reuse cycles.

Tailoring graphene-oxide and reduced-graphene-oxide with NaNO3 and CaCl2 catalysts with enhanced photo-catalytic degradation of methylene blue dye.

This study employed various experimental techniques to produce graphene oxide (GO) under different conditions, such as the inclusion or exclusion of NaNO3, and reduced graphene oxide (RGO) with or without the catalyst CaCl2. The procedure of decreasing RGO was carried out using the reducing agent NaBH4. Moreover, the prepared mixtures were utilized in the degradation process of methylene blue (MB) dye using photo-catalysis, with exposure to both ultraviolet (UV) light and sunlight. When exposed to UV and sunlight irradiation, WN-GO showed rapid and ecologically friendly breakdown of MB dye in comparison to N-GO. WN-GO exhibited exceptional adsorption capabilities, surpassing other tested materials like N-GO, WN-C-RGO and C-RGO. Although WN-C-RGO has demonstrated satisfactory performance in terms of photo-catalytic degradation, as the concentration-time graph of the MB dye revealed significant degradation, with a reduction of up to 90% and 62.5% under UV light and sunlight exposure, respectively. These results offer insightful information on the potential of graphene-based materials to address other environmental issues, particularly in the areas of water treatment.

Rocephin-graphene oxide-silver nanocomposites: A versatile platform for biomedical applications.

For many years, the synthesis of graphene oxide (GO) had involved exfoliating graphite flakes, and the methods applied were expensive and time-consuming. Thus, an attempt had been made to create an inventive, less expensive method for the synthesis of GO using unrefined, raw carbon-containing material. Modified Hummer's method was used to prepare GO from banana peel. In addition, the metallic silver nanocomposite was also synthesized along with laoding of drug Rocephin where they interact with each other through electrostatic hydrogen bond interaction. The degree of crystallinity and the crystallite size were through x-ray diffraction (XRD) analysis and the crystallite size of AgNPs was found to be 40.40 nm. The scanning electron microscopy (SEM) analysis shows that the morphology of the GO gradually changes with the addition of AgNPs and Rocephin. A blue shift was seen in the absorbance maxima of the raw carbon upon the conjugation of Rocephin in UV analysis. The Fourier-transform infrared spectroscopy, and energy dispersive X-ray (EDX) spectroscopy were used to determine the chemical composition of the samples. Furthermore, a broad biological screening of the synthesized samples had been carried out following the total reducing power (TRP), total antioxidant capacity (TAC), antibacterial, antifungal, MTT (Cytotoxicity of biologically synthesized silver nanoparticles in MDA-MB-231 human breast cancer cells) cell viability, brine shrimp lethality, and hemolytic protocols. Significant results were obtained, and the Rocephin-GO-AgNPs had depicted promising activity as compared with their counterparts. RESEARCH HIGHLIGHTS: The GO was prepared from the raw carbon extracted from banana peels and was used as a substrate for the synthesis Graphene oxide silver nanoparticles (GO-AgNPs) and Rocephin-loaded graphene oxide silver nanoparticles (Rocephin-GO-AgNPs) The structural and compositional analysis of the nanomaterial was carried out, and they were screened for several biomedical applications. The Rocephin-GO-AgNPs exhibit the highest activity as compared with their counterparts.

Qualitative and Quantitative Investigation of Biochar-Cu0 Composite for Nickel Adsorption.

The current investigation deals with the treatment of water pollution that is caused by the leaching of nickel ions from the metallurgical industry and new-energy batteries. Therefore, an eco-friendly treatment of nickel through the use of a composite of cotton stalk biochar with nanozerovalent copper has been presented in this investigation signifying the impact of zerovalent copper in enhancing the adsorption capacity of biochar for nickel adsorption. Thermogravimetric analysis data showed the adsorbent to be significantly stable in the higher thermal range, whereas transmission electron microscopy analysis confirmed the particles to be 27 nm and also showed the cubic geometry of the particles. A much closer scanning electron microscopy analysis shows the morphology of particles to be cubic in shape. Batch adsorption indicated a positive influence of pH increase on adsorption due to the electrostatic attraction between positive nickel ions and post point of zero charge (pHPZC) negative surface of copper biochar composite (pH > 5.5). A high adsorption rate was observed in the first 60 min, whereas adsorption increased with the increase in temperature from 303 to 318 K. Kinetic modeling confirmed the pseudo-first-order to fit best to the data. The apparent activation energy (11.96 kJ mol-1) is indicative of the chemical nature of the process. The adsorption data fitted well to the Langmuir adsorption model. The negative values of apparent ΔG° and the positive values of apparent ΔH° indicate the spontaneity and endothermicity of the process, respectively, whereas the positive values of apparent ΔS° point toward increased randomness during the process. Postadsorption XPS suggests the adsorption of nickel on the surface of biochar composites in the form of Ni(OH)2 and NiO(OH).

Montmorillonite modified Ni/Mg/Al ternary layered double hydroxide nanoflowers with enhanced adsorption features.

A hydrothermal technique was employed to synthesize Ni/Mg/Al ternary L.D.H.s modified with montmorillonite (NMA-MMT-LDHs). Many characterization methods, including X-ray diffraction (XRD), scanning electron microscopy (S.E.M.), Fourier transform infrared (FTIR), and Brunauer, Emmett, and Teller (B.E.T.), were used to assess the physiochemical properties of the produced analytes. Congo red and methylene blue were utilized as model dyes to treat textile waste with the synthesized analytes. The batch adsorption model was utilized to conduct the adsorption experiments under varying contact time, adsorbent dosage, and solution pH conditions. A pseudo-second-order kinetics and the Langmuir adsorption model control the adsorption process. The maximum monolayer adsorption capacities of C.R. and M.B. were determined to be 344 and 200 mg/g, respectively. As the quantity of dosage increased from the 0.01-0.04 g, the percent removal efficiency (%) increased from 75 to 87 % for S2-LDH, 84-88 % for S2-MMT, 86-93 % for S3-MMT, and 95-97% for S4-MMT for C.R. dye and 82-85 % for S2-LDH, 83-89 % for S2-MMT, 83-91 % for S3-MMT, and 84-92 % for S4-MMT for M.B. dye. The removal percentage of C.R. dye for adsorbents S2-LDH, S2-MMT, S3-MMT, and S4-MMT were 75 %, 84 %, 86 %, and 95 %, respectively and 82 %, 83 %, 83 %, and 85 %, respectively for the M.B. dye removal. The presence of MMT significantly increases the affinity of Ni/Mg/Al-LDHs (NMA-LDHs), and the designed production technique can be used to produce a variety of compositionally distinct adsorbent materials.

Porous Hierarchical Ni/Mg/Al Layered Double Hydroxide for Adsorption of Methyl Orange from Aqueous Solution.

A basic urea technique was successfully used to synthesize Mg/Al-Layered double hydroxides (Mg/Al LDHs), which were then calcined at 400 °C to form Mg/Al-Layered double oxides (Mg/Al LDOs). To reconstruct LDHs, Mg/Al LDOs were fabricated with different feeding ratios of Ni by the co-precipitation method. After synthesis, the Ni/Mg/Al-layered double hydroxides (NMA-LDHs) with 20% and 30% Ni (S1 and S2) were roasted at 400 °C and transformed into corresponding Ni/Mg/Al-layered double oxides (NMA-LDOs) (S1a and S2b, respectively). The physiochemical properties of synthesized samples were also evaluated by various characterization techniques, such as X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared (FTIR), and Brunauer, Emmett, and Teller (BET). The adsorption behavior of methyl orange (MO) onto the synthesized samples was evaluated in batch adsorption mode under varying conditions of contact time, adsorbent quantity, and solution pH. As the dosage amount increased from 0.01-0.04 g, the removal percentage of MO dye also increased from 83% to 90% for S1, 84% to 92% for S1a, 77% to 87% for S2, and 93% to 98% for S2b, respectively. For all of the samples, the adsorption kinetics were well described by the pseudo-second-order kinetic model. The equilibrium adsorption data were well fitted to both Langmuir and Freundlich models for methyl orange (MO). Finally, three adsorption-desorption cycles show that NMA-LDHs and NMA-LDOs have greater adsorption and reusability performance for MO dye, signifying that the design and fabrication strategy can facilitate the application of the natural hydrotalcite material in water remediation.

Synthesis and characterization of Ag2O, CoFe2O4, GO, and their ternary composite for antibacterial activity.

Currently, nanomaterials with exceptional antibacterial activity have become an emerging domain in research. The optimization of nanomaterials against infection causing agents is the next step in dealing with the present-day problem of antibiotics. In this research work, Ag2O, CoFe2O4, and Ag2O/CoFe2O4/rGO are prepared by chemical methods. Ag2O was prepared by co-precipitation method, while solvothermal technique was utilized for the synthesis of CoFe2O4. The ternary nanocomposite was synthesized by a simple in situ reduction using a two-step approach. The structural and morphological properties were studied by UV-Vis spectroscopy, X-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (SEM), dynamic light scattering (DLS), and Fourier-transform infrared spectroscopy (FTIR). From the X-ray diffraction analysis, the crystallite size is found to be 14 nm, 5 nm, and 6 nm for Ag2O, CoFe2O4, and Ag2O/CoFe2O4/rGO respectively. The synthesized nanomaterials were investigated for antibacterial activities against gram-positive strain Staphylococcus aureus (S. aureus) and gram-negative strain Escherichia coli (E. coli) using Agar well diffusion method. Ag2O and CoFe2O4 showed zones of inhibition (ZOI) of 13 mm and 11 mm against gram positive bacteria while 12 mm against gram negative bacteria respectively, while ternary nanocomposite showed 14 mm and 13 mm of ZOI. The antibacterial activity of nanomaterials showed a gradual increment with an increase in the concentration of the materials. Ag2O, CoFe2O4, and Ag2O/CoFe2O4/rGO showed minimum inhibitory concentration (MIC) values of 4.5, 6.5, and 4.5 µg/mL for S. aureus and 6.5, 7.2, and 4.8 µg/mL for E. coli respectively. Minimum bactericidal concentrations were found to be same as the MIC values. Additionally, a time-kill curve analysis was performed and for ternary nanocomposite; the killing response was most effective as the complete killing was achieved at 3 h of incubation at 3-MIC (9.75 µg/mL). These results demonstrate that all the nanomaterials, as a kind of antibacterial material, have a great potential for a wide range of biomedical applications.

Green Synthesis of NiO-SnO2 Nanocomposite and Effect of Calcination Temperature on Its Physicochemical Properties: Impact on the Photocatalytic Degradation of Methyl Orange.

Background: Nickel stannate nanocomposites could be useful for removing organic and toxic water pollutants, such as methyl orange (MO). Aim: The synthesis of a nickel oxide-tin oxide nanocomposite (NiO-SnO2 NC) via a facile and economically viable approach using a leaf extract from Ficus elastica for the photocatalytic degradation of MO. Methods: The phase composition, crystallinity, and purity were examined by X-ray diffraction (XRD). The particles' morphology was studied using scanning electron microscopy (SEM). The elemental analysis and colored mapping were carried out via energy dispersive X-ray (EDX). The functional groups were identified by Fourier transform infrared spectroscopy (FTIR). UV-visible diffuse reflectance spectroscopy (UV-vis DRS) was used to study the optical properties such as the absorption edges and energy band gap, an important feature of semiconductors to determine photocatalytic applications. The photocatalytic activity of the NiO-SnO2 NC was evaluated by monitoring the degradation of MO in aqueous solution under irradiation with full light spectrum. The effects of calcination temperature, pH, initial MO concentration, and catalyst dose were all assessed to understand and optimize the physicochemical and photocatalytic properties of NiO-SnO2 NC. Results: NiO-SnO2 NC was successfully synthesized via a biological route using F. elastica leaf extract. XRD showed rhombohedral NiO and tetragonal SnO2 nanostructures and the amorphous nature of NiO-SnO2 NC. Its degree of crystallinity, crystallite size, and stability increased with increased calcination temperature. SEM depicted significant morphological changes with elevating calcination temperatures, which are attributed to the phase conversion from amorphous to crystalline. The elemental analysis and colored mapping show the formation of highly pure NiO-SnO2 NC. FTIR revealed a decrease in OH, and the ratio of oxygen vacancies at the surface of the NC can be explained by a loss of its hydrophilicity at increased temperatures. All the NC samples displayed significant absorption in the visible region, and a blue shift is seen and the energy band gap decreases when increasing the calcination temperatures due to the dehydration and formation of compacted large particles. NiO-SnO2 NC degrades MO, and the photocatalytic performance decreased with increasing calcination temperature due to an increase in the crystallite size of the NC. The optimal conditions for the efficient NC-mediated photocatalysis of MO are 100 °C, 20 mg catalyst, 50 ppm MO, and pH 6. Conclusions: The auspicious performance of the NiO-SnO2 NCs may open a new avenue for the development of semiconducting p-n heterojunction catalysts as promising structures for removing undesirable organic pollutants from the environment.

Enhanced Thermal Stability and Synergistic Effects of Magnesium and Iron Borate Composites against Pathogenic Bacteria.

A simple process based on the dual roles of both magnesium oxide (MgO) and iron oxide (FeO) with boron (B) as precursors and catalysts has been developed for the synthesis of borate composites of magnesium and iron (Mg2B2O5-Fe3BO6) at 1200°C. The as-synthesized composites can be a single material with the improved and collective properties of both iron borates (Fe3BO6) and magnesium borates (Mg2B2O5). At higher temperatures, the synthesized Mg2B2O5-Fe3BO6 composite is found thermally more stable than the single borates of both magnesium and iron. Similarly, the synthesized composites are found to prevent the growth of both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) pathogenic bacteria on all the tested concentrations. Moreover, the inhibitory effect of the synthesized composite increases with an increase in concentration and is more pronounced against S. aureus as compared to E. coli.

Adsorption and Kinetics Studies of Cr (VI) by Graphene Oxide and Reduced Graphene Oxide-Zinc Oxide Nanocomposite.

In this work, graphene oxide (GO) and its reduced graphene oxide-zinc oxide nanocomposite (rGO-ZnO) was used for the removal of Cr (VI) from aqueous medium. By employing a variety of characterization techniques, morphological and structural properties of the adsorbents were determined. The adsorption study was done by varying concentration, temperature, pH, time, and amount of adsorbent. The results obtained confirmed that rGO-ZnO is a more economical and promising adsorbent for removing Cr (VI) as compared to GO. Kinetic study was also performed, which suggested that sorption of Cr (VI) follows the pseudo-first-order model. For equilibrium study, non-linear Langmuir was found a better fitted model than its linearized form. The maximum adsorption capacity calculated for GO and rGO-ZnO nanocomposite were 19.49 mg/g and 25.45 mg/g, respectively. Endothermic and spontaneous nature of adsorption was detected with positive values of ΔS (change in entropy), which reflects the structural changes happening at the liquid/solid interface.

Investigations into the Antifungal, Photocatalytic, and Physicochemical Properties of Sol-Gel-Produced Tin Dioxide Nanoparticles.

Transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), and Fourier transform infrared (FTIR) spectroscopy were applied to evaluate the tin dioxide nanoparticles (SnO2 NPs) amalgamated by the sol-gel process. XRD was used to examine the tetragonal-shaped crystallite with an average size of 26.95 (±1) nm, whereas the average particle size estimated from the TEM micrograph is 20.59 (±2) nm. A dose-dependent antifun3al activity was performed against two fungal species, and the activity was observed to be increased with an increase in the concentration of SnO2 NPs. The photocatalytic activity of SnO2 NPs in aqueous media was tested using Rhodamine 6G (Rh-6G) under solar light illumination. The Rh-6G was degraded at a rate of 0.96 × 10-2 min for a total of 94.18 percent in 350 min.

Synthesis and In Vitro/Ex Vivo Characterizations of Ceftriaxone-Loaded Sodium Alginate/poly(vinyl alcohol) Clay Reinforced Nanocomposites: Possible Applications in Wound Healing.

(1) Background: Nanocomposite films are widely applied in the pharmaceutical industry (e.g., nanodrug delivery systems-NDDS). Indeed, these nanomaterials can be produced at a large industrial scale and display valuable properties (e.g., antibacterial, renewability, biodegradability, bioavailability, safety, tissue-specific targeting, and biocompatibility), which can enhance the activity of conventional marketed drugs. (2) Aim: To fabricate and investigate the in vitro properties of the antibiotic ceftriaxone sodium (CTX) once encapsulated into sodium alginate (SA)/poly(vinyl alcohol)PVA-clay reinforced nanocomposite films. (3) Methods: Different ratios of the polymers (i.e., SA, PVA) and CTX drug were used for the synthesis of nanocomposite films by solvent casting technique. Montmorillonite (MMT), modified organically, was added as a nanofiller to increase their thermal and mechanical strength. The prepared samples were physically characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electronic microscopy (SEM), and energy-dispersive X-ray analysis (EDX). The physicochemical behavior (i.e., swelling, erosion, dissolution/drug release behavior and rat skin permeation) was also assessed. Comparisons were made with the currently marketed free CTX dosage form. (4) Results: TGA of the nanoformulation showed increased thermostability. XRD revealed its semi-crystalline nature. SEM depicted a homogeneous drug-loaded SA/PVA nanocomposite with an average size ranging between 300 and 500 nm. EDX confirmed the elemental composition and uniform distribution of mixing components. The water entrapment efficiency study showed that the highest swelling and erosion ratio is encountered with the nanoformulations S100(3) and S100D15(3). Ex vivo permeation revealed a bi-step discharge mode with an early burst liberation chased by continued drug discharge of devised nanoparticles (NPs). The dissolution studies of the drug-loaded polymer nanocomposites elicited sustained pH-dependent drug release. The cumulative drug release was the highest (90.93%) with S100D15(3). (5) Conclusion: S100D15(3) was the finest formulation. To the best of our knowledge, we also pioneered the use of solvent casting for the preparation of such nanoformulations. Polymers and reinforcing agent, concentrations and pH were rate-deterring features for the preparation of the optimized formulation. Thus, CTX-loaded SA/PVA-MMT reinforced nanocomposite appeared as a promising nanodrug delivery system (NDDS) based on its in vitro physicochemical properties.

Numerical Solutions of Variable Coefficient Higher-Order Partial Differential Equations Arising in Beam Models.

In this work, an efficient and robust numerical scheme is proposed to solve the variable coefficients' fourth-order partial differential equations (FOPDEs) that arise in Euler-Bernoulli beam models. When partial differential equations (PDEs) are of higher order and invoke variable coefficients, then the numerical solution is quite a tedious and challenging problem, which is our main concern in this paper. The current scheme is hybrid in nature in which the second-order finite difference is used for temporal discretization, while spatial derivatives and solutions are approximated via the Haar wavelet. Next, the integration and Haar matrices are used to convert partial differential equations (PDEs) to the system of linear equations, which can be handled easily. Besides this, we derive the theoretical result for stability via the Lax-Richtmyer criterion and verify it computationally. Moreover, we address the computational convergence rate, which is near order two. Several test problems are given to measure the accuracy of the suggested scheme. Computations validate that the present scheme works well for such problems. The calculated results are also compared with the earlier work and the exact solutions. The comparison shows that the outcomes are in good agreement with both the exact solutions and the available results in the literature.

In-vivo toxicity and therapeutic efficacy of Paeonia emodi-mediated zinc oxide nanoparticles: In-vitro study.

This study was planned to explore the in-vitro and in-vivo therapeutic significance of Paeonia emodi-mediated zinc oxide nanoparticles (ZnO NPs) against the Staphylococcus aureus and Escherichia coli. The texture parameters were derived from nitrogen adsorption-desorption data using Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) methods, and the surface area (SBET ) was found to be 214 m2 /g with a pore size of 2.3 nm. The crystallographic parameters were investigated through X-ray diffraction analysis, and the calculated crystallite size is 29.13 nm. The microstructure was examined through transmission and scanning electron microscopies (TEM and SEM, respectively), and the average particle size estimated from a TEM image is 44.40 nm. The chemical composition and attached function groups were identified through energy-dispersive X-ray and Fourier transform infrared spectroscopies. The in-vitro minimum inhibitory concentration (MIC) for both bacterial species results was found less than 2 µg/ml. The tolerance limit of mouse models was evaluated by the inoculation of different concentrations of ZnO suspension where the concentration above 23 ppm was proved lethal. The maximum infection was caused in mouse models by inoculation of 3 × 107 CFUs (Colony forming unit) of the both bacterial species. The concentration higher than 3 × 107 CFUs led to the ultimate death of the mice. The histopathological and hematological studies reveal that the after simultaneous inoculation of both ZnO NPs and bacterial suspensions (tolerated amount), no/negligible infection was found in the mice model.

Bergenia ciliate-Mediated Mixed-Phase Synthesis and Characterization of Silver-Copper Oxide Nanocomposite for Environmental and Biological Applications.

Bergenia ciliate (B. ciliate) leaf extract was used as a reducing and stabilizing agent for the synthesis of silver-copper oxide nanocomposite (Ag-CuO NC). Scanning and transmission electron microscopies (SEM and TEM) were used to examine the structural morphology, and the average particle size was determined to be 47.65 nm. The phase confirmation and crystalline structure were examined through the X-ray diffraction (XRD) technique, where cubic and monoclinic geometries were assigned to Ag and CuO. The energy dispersive X-ray (EDX), Fourier transform infrared (FTIR) and ultra-violet and visible (UV-Visible) spectroscopies were operated to analyse the elemental composition, functional groups and light absorption phenomena of the Ag-CuO NC. Under the full light spectrum, the photodegradation of Rhodamine 6G was recorded, and 99.42 percent of the dye degraded in 80 min. The Agar well diffusion method was followed to perform antibacterial activity against selected pathogens, and the activity was found to increase with increasing concentration of Ag-CuO NC. The ABTS free radical scavenging activity suggests that the activity of Ag-CuO NC is higher than ascorbic acid.

In-Vitro and In-Vivo Tolerance and Therapeutic Investigations of Phyto-Fabricated Iron Oxide Nanoparticles against Selected Pathogens.

The Paeonia emodi (P. emodi)-mediated iron oxide nanoparticles (Fe2O3 NPs) were screened for in-vitro and in-vivo antibacterial activity against the Staphylococcus aureus (S. aureus) (ATCC #: 6538) and Escherichia coli (E. coli) (ATCC #:15224). The synthesized Fe2O3 NPs were characterized via nitrogen adsorption-desorption process, X-ray diffractometer (XRD), transmission and scanning electron microscopies (TEM and SEM), energy dispersive X-ray (EDX) and Fourier transform infrared (FTIR) spectroscopies. The SBET was found to be 94.65 m2/g with pore size of 2.99 nm, whereas the average crystallite and particles size are 23 and 27.64 nm, respectively. The 4 µg/mL is the MIC that inhibits the growth of E. coli, whereas those for S. aureus are below the detection limit (<1.76 µg/mL). The tolerance limit of the mice model was inspected by injecting different concentration of Fe2O3 NPs and bacteria suspensions. The 14 ppm suspension was the tolerated dose and the concentration above were proved lethal. The most severe infection was induced in mice with injection of 3 × 107 CFUs of both bacteria, while the inoculation of higher concentrations of bacterial suspensions resulted in the mice's death. The histopathological and hematological studies reveals that the no/negligible infection was found in the mice exposed to the simultaneous inoculation of Fe2O3 NPs (14 ppm) and bacterial suspensions (3 × 107 CFUs).

Novel nanocomposite of biochar-zerovalent copper for lead adsorption.

In this study, a composite of zerovalent copper-biochar was investigated for its ability to remove lead from water. The prepared material was characterized by using scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), X-ray diffractomter (XRD), and X-ray photoelectron spectroscopy (XPS). The pH effect on adsorption of lead was investigated within the range of 2-8 and the effect of temperature was studied at 303, 308, 313, and 318 K. The kinetics of lead adsorption on biochar composite was evaluated and the equilibrium time of 12 hr was established. To further evaluate the nature of adsorption, Langmuir model was tested and the adsorption capacities were evaluated for lead adsorption on the surface of copper biochar composite. The activation energy, entropy, and enthalpy values indicated the adsorption phenomenon to be chemisorptive and spontaneous in nature. Comparison of adsorption capacities with the reported adsorbents in the literature concluded zerovalent copper-biochar composite to be an efficient adsorbent for the removal of lead in the experimental conditions under study. RESEARCH HIGHLIGHTS: Highly efficient composite of zerovalent copper with biochar was synthesized for lead adsorption. XPS and XRD shows the presence of zerovalent copper in the biochar composite. pH and temperature were the main governing factors in the adsorption process. Adsorption capacity for lead is higher than many of the reported adsorbents.

Structural and biological investigation of biogenically synthesized titanium dioxide nanoparticles: Calcination and characterization.

The antimicrobial drug resistance is increasing with the passage of time due to wide and improper use of broad spectrum drugs and the demand of the new drug increases day by day. The present study was planned to encounter this problem by synthesizing titanium dioxide nanoparticles (TiO2 NPs) by an eco-friendly route using Cannabis sativa leaves extract. The synthesized TiO2 NPs were calcined at 100, 300, 600, and 900°C in a muffle furnace. The crystallographic parameters were studied by X-ray diffraction and the phase transition occurred above 600°C. The surface morphology of the synthesized samples was studied by transmission electron microscopy (TEM), and scanning electron microscopy (SEM) and the particle size was measured through the ImageJ software. The elemental composition and purity of all the samples were studied by performing energy dispersive X-ray (EDX). All the synthesized TiO2 NPs were tested for their antimicrobial effect against Gram-positive and Gram-negative bacteria using the agar well diffusion method. The activity was found higher against Gram-negative bacteria and compared to Gram-positive bacteria.

Populus ciliata mediated synthesis of silver nanoparticles and their antibacterial activity.

Design and synthesis of bactericidal and fungicidal agents is very important to protect human beings from different diseases. Silver nanoparticles (AgNPs) possess good bactericidal properties. Synthesis of these nanoparticles (NPs) via green route is cost-effective and environmentally harmonious as compared to the chemical and physical approaches. In this work, AgNPs were synthesized through green synthesis method using Populus ciliata leaf extract. The synthesized AgNPs were characterized by x-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive x-ray (EDX) techniques. The XRD pattern depicted the characteristic Bragg's peaks of (111), (200), (220), and (311) planes which are the features of face centered cubic (FCC) geometry of the synthesized AgNPs. TEM micrographs revealed the spherical shaped particles having average size of 4 nm. The AgNPs showed inhibitory effects against selected gram positive (Staphylococcus epidermidis and Streptococcus pyogenes) and gram negative bacteria (Klebsiella pneumoniae, Serratia marcescens, and Pseudomonas pseudoalcaligenes). The maximum zone of inhibition (26 mm) was observed for gram negative bacterium (Serratia marcescens) when 25 mg/ml solution of AgNPs was used and for similar concentration of these NPs, the maximum zone of inhibition (25 mm) was observed against gram positive bacteria (S. pyogenes). The results indicated good bactericidal potential of the synthesized AgNPs. RESEARCH HIGHLIGHTS: Populus ciliata leaf extract mediated synthesis of AgNPs. Transmission electron microscopy analysis revealed very small size of the synthesized AgNPs (4 nm). The synthesized AgNPs were found very effective against various bacterial pathogens.

Synthesis of enriched boron nitride nanocrystals: A potential element for biomedical applications.

The shortcomings in Boron neutron capture therapy (BNCT) and Hyperthermia for killing the tumor cell desired for the synthesis of a new kind of material suitable to be first used in BNCT and later on enable the conditions for Hyperthermia to destroy the tumor cell. The desire led to the synthesis of large band gap semiconductor nano-size Boron-10 enriched crystals of hexagonal boron nitride (10BNNCs). The contents of 10BNNCs are analyzed with the help of x-ray photoelectron spectroscopy (XPS) and counter checked with Raman and XRD. The 10B-contents in 10BNNCs produce 7Li and 4He nuclei. A Part of the 7Li and 4He particles released in the cell is allowed to kill the tumor (via BNCT) whereas the rest produce electron-hole pairs in the semiconductor layer of 10BNNCs suggested to work in Hyperthermia with an externally applied field.