Chemical Co-precipitation Method Research Articles

Synthesis and Characterization of ZnS Nanoparticles by Chemical Co-precipitation Method

ZnS nanomaterials were effectively synthesized by the chemical co-precipitation method by using Zinc Acetate (Zn (CH3COO)2·2H2O), sodium sulfide (Na2S) and Poly Vinyl Pyrollidine (PVP) as precursor materials. The reactions were carried out at ambient temperature. The X-ray diffraction (XRD) studies confirmed the cubic zinc blende shape of ZnS. Surface morphology of the prepared material was analyzed by scanning electron microscopic (SEM) and transmission electron microscopic (TEM) techniques. The average particle size of the ZnS is found to be around 2 to 3 nm. Optical studies were carried out to calculate band gap energy by using UV-visible spectroscopy. The band gap energy of prepared ZnS nanoparticles is found to be as 3.7 eV.

Exploration of Bifunctionality in Mn, Co Codoped CuO Nanoflakes for Overall Water Splitting

Herein, bimetal (Mn, Co) codoping on a CuO host is aimed at enhancing oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) activity. Codoping of Mn and Co on CuO to enhance bifunctional action in electrochemical water splitting has not yet been investigated to the best of our knowledge. Literatures are focused on unary Mn-doped CuO or Co-doped CuO nanostructures. Mn, Co codoped CuO through an easy chemical coprecipitation method has been successfully attempted and is more beneficial which is the novelty of the present work. Defect-enriched ample active sites (Mn2+/Mn3+ and Co2+/Co3+) along with Cu2+ in the host CuO achieved high current density (100 mA/cm2) in OER and HER with low overpotential such as 468 mV and 271 mV, respectively. Faster charge transfer and diffusion ability was stimulated by the bimetal codoping CuO. Reasonable Tafel plot values (OER: 199 mV/dec, and HER: 21 mV/dec) with improved water-splitting reaction kinetics were achieved for the Mn, Co codoped CuO nanoflakes. The double-layer capacitance ( C dl ) value of 27.5 mF/cm2 for Mn, Co codoped CuO nanoflakes was achieved. Similarly, the increasing order of an electrochemically active surface area (EASA) was exhibited by the consequent addition of bimetal doping on CuO, denoted as Mn , Co / CuO > Co / CuO > Mn / CuO > CuO . The evidence shows that the codoping strategy could facilitate rapid reaction kinetics to develop overall water splitting. The charge transfer resistances ( R ct ) of 3.6 Ω and 1.2 Ω for the Mn, Co codoped CuO nanostructure corresponding to the OER and HER, respectively, were reported. The long-term stability over 16 h with negligible loss was reported for both the OER and the HER performance. Thus, this work contributes to better insight and analysis of the successful codoping of bimetal elements in earth-abundant electrocatalysts to enhance and make practical the electrocatalytic water-splitting activity.

Functionalized iron oxide nanoparticles for covalent immobilization of cellic CTec2 cellulase: enabling enzyme reusability in cellulosic biomass conversion

A modified chemical co-precipitation method was employed to synthesize silicacoated-aminefunctionalized iron oxide nanoparticle (IONP@SiO2-NH2) which has been utilized as an anchoring surface for enzyme immobilization. Cellulase Cellic CTec2 cocktail was immobilized covalently onto IONP@SiO2-NH2 using glutaraldehyde as a linker. The morphological, structural, and compositional studies of nanoparticles were characterized by field emission scanning electron microscopy with energy dispersive X-ray (FESEM)-EDX, Fourier transform infrared (FTIR), X-ray diffraction (XRD), zeta potential, and Ultraviolet/visible (UV-Vis) spectroscopy. The FTIR, FESEM, and XRD spectra confirmed the successful immobilization of cellulase onto IONP@SiO2-NH2. The free enzymewith cellulase activity of 127 FPU/mL was optimized for the immobilization process which showed the best binding efficiency at 2% glutaraldehyde, protein loading 100 mg/g with carboxymethyl cellulase activity of 290 IU/g, and total immobilization yield of 70.8%. The immobilized cellulase exhibited enhanced stability for temperature and pH over a broader rangethan the free enzyme. The immobilized enzyme-mediated hydrolysis of 1% carboxymethyl cellulose (CMC) released 0.54 g glucose/g substrate at 24 h, showing potential for cellulosic biomass conversion. The immobilized cellulase which was investigated for reusability assay retained∼80% activity even after repeated 6 cycles of CMC hydrolysis. The results showed good reusability after magnetic separation, which is the main advantage of using this nanobiocatalyst system.

TiO2, CeO2, and TiO2–CeO2 nanoparticles incorporated 2.5D chitosan hydrogels: Gelation behavior and cytocompatibility

In this study, gelation behavior and cytocompatibility of 2.5D chitosan hydrogels were investigated in the presence of TiO2, CeO2 and TiO2–CeO2 composite nanoparticles. Chemical co-precipitation method was used for nanoparticle synthesis and they were heat treated at 600 °C and 700 °C. Gelation of the chitosan solutions was carried out at 37 °C in the presence of glycerol phosphate and genipin as crosslinkers. The gelation time of chitosan was decreased by all of the nanoparticles whereas its elastic modulus was increased by nanoparticles addition. Chitosan solutions containing CeO2 or TiO2–CeO2 nanoparticles showed faster gel formation compared to chitosan solutions containing only TiO2 nanoparticles. CeO2@700 °C nanoparticles decreased the gelation time by 46% and increased elastic modulus by 14%. Average pore diameter of the hydrogel decreased from 127 ± 62 μm to 77 ± 33 μm, water uptake decreased 21% and thermal stability increased in the presence of CeO2@700 °C nanoparticles compared to chitosan hydrogel. Cell viability results indicated that chitosan hydrogels with or without nanoparticles created 2.5D environment supporting cellular proliferation approximately 1.5 times more than TCPS due to their high porous surfaces. Immunofluorescence images were also supported cell viability results. Therefore, CeO2 or TiO2–CeO2 composite nanoparticles incorporated 2.5D chitosan hydrogels may be alternative tissue engineering materials with their fast gelation, ease of use, low cost, light transparency, and cytocompatibility.

Structural evolution, synthesis mechanism and thermal conductivity of (La0.2Nd0.2Sm0.2Gd0.2Yb0.2)2Zr2O7 high-entropy ceramic prepared by concurrent chemical coprecipitation method

(La0.2Nd0.2Sm0.2Gd0.2Yb0.2)2Zr2O7 (Ln2Zr2O7) ceramic powders with nanoscale were synthesized by concurrent chemical coprecipitation method. The thermal behaviors and structural evolution of Ln2Zr2O7 precursor were investigated. The synthesis mechanism and thermal conductivity of Ln2Zr2O7 ceramic were also discussed in detail. Results show that a kind of complex polymeric compound containing -[Zr–OH–Zr]- and -[Zr–OH-Ln]- network structure was formed in the as-synthesized Ln2Zr2O7 precursor, which directly transformed to Ln2Zr2O7 crystals through dehydroxylation and structural ordering during the calcination process. The bulk Ln2Zr2O7 ceramics have a lower thermal conductivity of 1.20–1.47 W/(m·K), which can be attributed to the high-entropy effect resulting from the introduction of multiple rare earth elements.

Synthesized Fe-doped Co3O4 nanoparticles-based anode for high-performance lithium-ion batteries application

ABSTRACT Co3O4 has been considered a promising anode material because of its high theoretical capacity (890 mAh/g) and remarkable energy density. Unfortunately, it suffers from low initial coulombic efficiency, rapid capacity fading, poor electronic conductivity, large volume changes, and aggregation during the lithium ion intercalation/deintercalation process. In this work, a series of Fe2+-doped Co3O4 nanostructured materials Co3(1-x)Fe3xO4 (x = 0, 0.01, 0.02 and 0.03) were produced by a simple chemical co-precipitation method. The Fe doping led to a slight increase of the lattice parameter, which is beneficial to the rapid diffusion of Li+ ion during the lithiation/delithiation process. Meanwhile, the Fe-doped Co3O4 sample exhibited an excellent rate capability of 886.47 mAh/g at 500 mA/g, and outstanding cyclic stability (1156.91 mAh/g for 50 cycles, with the capacity retention rate of 83.53% at the current density of 100 mA/g), demonstrating improved electrochemical performance, compared with that of pure Co3O4. The good electrochemical performance profited from the formation of oxygen vacancies by Fe doping, which provided more space for Li+ diffusion and improved the electronic conductivity of the anode material. This work provides a simple way to improve the comprehensive electrochemical performance of the transitional metal oxide Co3O4 anode electrodes for lithium-ion batteries.

Cerium(IV) chitosan-based hydrogel composite for efficient adsorptive removal of phosphates(V) from aqueous solutions

The excess presence of phosphate(V) ions in the biosphere is one of the most serious problems that negatively affect aqueous biocenosis. Thus, phosphates(V) separation is considered to be important for sustainable development. In the presented study, an original cerium(IV)-modified chitosan-based hydrogel (Ce-CTS) was developed using the chemical co-precipitation method and then used as an adsorbent for efficient removal of phosphate(V) ions from their aqueous solutions. From the scientific point of view, it represents a completely new physicochemical system. It was found that the adsorptive removal of phosphate(V) anions by the Ce-CTS adsorbent exceeded 98% efficiency which is ca. 4-times higher compared with the chitosan-based hydrogel without any modification (non-cross-linked CTS). The best result of the adsorption capacity of phosphates(V) on the Ce-CTS adsorbent, equal to 71.6 mg/g, was a result of adsorption from a solution with an initial phosphate(V) concentration 9.76 mg/dm3 and pH 7, an adsorbent dose of 1 g/dm3, temperature 20 °C. The equilibrium interphase distribution data for the Ce-CTS adsorbent and aqueous solution of phosphates(V) agreed with the theoretical Redlich-Peterson and Hill adsorption isotherm models. From the kinetic point of view, the pseudo-second-order model explained the phosphates(V) adsorption rate for Ce-CTS adsorbent the best. The specific effect of porous structure of adsorbent influencing the diffusional mass transfer resistances was identified using Weber-Morris kinetic model. The thermodynamic study showed that the process was exothermic and the adsorption ran spontaneously. Modification of CTS with cerium(IV) resulted in the significant enhancement of the chitosan properties towards both physical adsorption (an increase of the point of zero charge of adsorbent), and chemical adsorption (through the presence of Ce(IV) that demonstrates a chemical affinity for phosphate(V) anions). The elaborated and experimentally verified highly effective adsorbent can be successfully applied to uptake phosphates(V) from aqueous systems. The Ce-CTS adsorbent is stable in the conditions of the adsorption process, no changes in the adsorbent structure or leaching of the inorganic filling were observed.

Phase evolution and hot corrosion behavior of Yb2O3 and CeO2 co-doping YSZ ceramics under high temperature

The phase instability of 6–8 wt% Y2O3 partially stabilized ZrO2 (YSZ) in high temperature and molten salt corrosion environment seriously limits its application above 1200 °C. In this study, the chemical co-precipitation method prepared Yb2O3 and CeO2 co-doping YSZ (YbCeYSZ) ceramic materials to improve the above issues. It was proposed to improve the defect of high-temperature phase instability of CeO2-doped YSZ materials by adding Yb2O3. The phase stability, thermal insulation properties, and Na2SO4 + V2O5 molten salt corrosion behavior of YbCeYSZ ceramic materials were studied. The results showed that 2.5 mol% Yb2O3-4 mol% CeO2-YSZ material (2.5Yb4CeYSZ) had no monoclinic phase (m-ZrO2) after holding at 1500 °C for 120 h due to forming more defect clusters in the system. Meanwhile, the 2.5Yb4CeYSZ had excellent thermal insulation performance and molten salt corrosion resistance, which was attributed to the strong phonon scattering in the 2.5Yb4CeYSZ material system and the low reactivity between the stabilizer and the corrosive salt.

FeCa-based layered double hydroxide, a high-performance phosphorus adsorbent in constructed wetlands and ecological dams - A pilot scale study

Research studies have modified traditional substances to seek fast-acting removal of phosphorus in constructed wetlands (CWs) and ecological dams, rather than develop a brand-new nano-adsorbent. This work synthesized FeCa-based layered double hydroxide (FeCa-LDH) with a chemical co-precipitation method, and the performance, mechanism and factors of phosphorus removal were investigated. FeCa-LDH showed a marked ability to adsorb phosphorus from waste water, with a removal efficiency of 94.4% and 98.2% in CWs and ecological dams, respectively. Both FTIR and XPS spectrum evidenced that FeCa-LDH removed phosphorus via electrostatic and hydrogen-bonding adsorption, as well as a coordination reaction and interlayer anion exchange. FeCa-LDH showed a higher capacity to remove phosphorus in alkaline and neutral waste water than in acid conditions. Co-occurrence anions, which influenced the efficiency of the phosphorus removal capacity are considered in the sequence below: CO32− ≈ HCO3− > SO42− > NO3−. Innovatively, FeCa-LDH was not affected by the low-temperature limitation for CWs, and phosphorus removal efficiency at 5 °C was almost equal to that at 25 °C. These results cast a new idea on the construction, application and phosphorus removal performance of CWs and ecological dams.

Hierarchical α-MoO3: A versatile eco-friendly material for humidity-assisted ammonia sensing and efficient catalytic activity in wastewater treatment

In this work, a facial synthesis of α-MoO3 nanoparticles was done by chemical co-precipitation method. The synthesized α-MoO3 nanomaterials have been reported for sensing and photocatalysis applications together. For sensing, the α-MoO3 was coated on FTO based interdigitated electrodes, and the prepared sensor was tested for numerous concentrations of ammonia (100–600 ppm) under different relative humidity levels (11–33%−56–75% −95% RH). The response and recovery time of α-MoO3 based sensor for 500 ppm of NH3 were 8 s and 11 s under 95% RH, respectively. The prepared α-MoO3 based sensor exhibits high selectivity and stability towards ammonia. To analyze the photocatalytic activity of prepared α-MoO3 nanoparticles, the photodegradation of methylene blue (MB) and methyl orange (MO) under visible light irradiation was studied. The first-order reaction rate constant for MB dye is 0.02434 min−1, and for MO dye is 0.01111 min−1. Finally, the maximum degradation efficiency for MB and MO dyes was calculated to be 95% and 73%, respectively. The given data conclude that the synthesized α-MoO3 nanoparticles can be used as an effective NH3 sensor as well as an efficient photocatalyst in organic dye degradation.

Evaluation of the reactivity of dense lanthanum‑gadolinium zirconate ceramics with Colima volcanic ashes

The effects of ingestion of airborne particles from pyroclastic events of active volcanoes by aircraft turbines and their subsequent reaction with thermal barrier coatings have attracted the attention of the scientific community in recent years. The reaction products of infiltration experiments of lanthanum‑gadolinium zirconate (LGZO) ceramics with molten ashes from the active Colima volcano at 1250 °C for 10 h are presented and discussed as a function of the Gd3+ content. Five ceramic compositions, varying the Gd3+ content in solid solution were synthesized by the chemical coprecipitation and calcination method of pressed powders. These compositions include pure lanthanum and gadolinium zirconates, LZO, and GZO, respectively. Penetration depth and identification, and in some cases quantification of the reaction products between the molten ash and LGZO ceramics were performed by scanning electron microscopy, chemical composition with energy dispersive X-ray spectroscopy, grazing incident X-ray diffraction as well as micro-Raman spectroscopy. The LZO ceramic exhibited the greatest infiltration resistance with an infiltration depth of approximately 23 μm from the surface. The phase characteristics of the reaction layers were dependent on the gadolinium content. LZO, LGZO25, and LGZO50 (x = 0, 0.25, and 0.5) showed the presence of apatite as well as monoclinic and tetragonal zirconia, while LGZO75 and GZO (x = 0.75 and 1), additionally showed the presence of cubic zirconia and anorthite. As the Gd3+ content increases in the LGZO solid solutions, the wavenumber value corresponding to the stretching vibrational mode of the silicon tetrahedra in apatite shifts from 862 to 877 cm−1, which is associated with a decrease in SiO bond lengths. These findings indicate that the amount and kind of rare earth cations dissolved in the melt plays an important role in the precipitation of the reaction products.

Potential use of coconut husk-based magnetic sorbent for defoaming application

Absorption process is the most common method that is being applied to sweeten sour gas in the oil and gas industry. However, this process does have several consequences which will trigger the foam formation of foam that will reduce the mass transfer efficiency and absorption capacity as well as amine solutions carryover to the downstream processes. The removal of undesired contaminants in activated methyldiethanolamine (MDEA) was conducted by utilizing magnetic activated carbon (MAC). In this work, MAC was synthesized from coconut husk through chemical activation and co-precipitation methods. The performance of this material as an adsorbent was evaluated based on the foaming behaviour of activated MDEA solvent after being contacted with MAC at different duration and varying amounts. Nitrogen gas was introduced into the solvent through a gas diffuser to create foam. Based on the results, the foam volume generated by activated MDEA solvent was identified to decrease with the increase in both MAC contact time and amount. The highest removal efficiency by MAC was identified to be at 1 h contact time between MAC and activated MDEA solvent where the foam breaking time was reduced to 10–30 min. Meanwhile, the addition of 50 % MAC into the solvent was able to further decrease the foam breaking time to 5–10 min. The characteristics of the prepared MAC were evaluated through various instrumental analyses. This study shows that the MAC synthesized from coconut husk has a good potential as an adsorbent in removing the contaminants in activated MDEA solvent to reduce foam formation.

Sono-enhanced heterogeneous Fenton catalysis: magnetic halloysite nanotube synthesis and accelerated free radical generation.

Although heterogeneous Fenton catalysis has captured increasing attention compared to its homogeneous counterpart, it still confronts some inherent drawbacks in use, such as the dilemma in solid-liquid separation and greater mass transfer resistance. Driven by the acoustic cavitation effect, herein, a sono-enhanced heterogeneous Fenton catalysis process was built to overcome the above two shortcomings, by rapidly synthesizing magnetic Fenton-like catalysts and accelerating electron transfer during the catalytic reaction. The results show that, compared to the traditional chemical coprecipitation method, Fe3O4 with smaller particle size and better crystallinity grew on the surface of halloysite nanotubes (HNTs) by using the sonochemical strategy, leading to displaying the higher catalytic activity toward the degradation of methylene blue (MB, improved by ~2.5 times). In parallel, more •OH and •O2- were produced after the ultrasound was further introduced to the routine Fenton-like catalysis system, thus highly accelerating the removal of MB (improved by ~50%). Besides, benefiting from the robust chemical integration of Fe3O4 and HNTs, Fe3O4@HNTs-S had a lower iron ion leaching in use, showing superior catalytic stability. The speed, simplicity, and generality, together with the enhanced mass transfer rate, make the use of ultrasound an enabling methodology to improve the heterogeneous Fenton catalysis.

Synthesis and application of Fe3O4/GO/PVP composite material for methylene blue adsorption

In this study, Fe3O4/GO/PVP (FGP) was successfully synthesized and efficiently applied for absorbing methylene blue. First, GO was synthesized by Hummer’s method from waste home-batteries. The chemical co-precipitation method was used to fabricate Fe3O4/GO from a mixture solution of GO, Fe3+, Fe2+. Polyvinylpyrrolidone PVP was selected to functionalize Fe3O4/GO and form Fe3O4/GO/PVP for improving dispersibility purpose in aqueous solution. The obtained Fe3O4/GO/PVP was characterized by XRD, FT-IR, BET, FE-SEM, UV-Vis techniques. Moreover, the effecting factors as pH, time adsorption, initial concentration of methylene blue were conducted. Adsorption isotherm models were also identified. The results showed that specific surface area of FGP-3 was 70.0 m2.g-1, the Freundlich isotherm model was suitable and the Dubinin - Radushkevich isotherm model showed that the process was physical adsorption. The maximum capacity (qmax) was 30.4 mg.g-1. These findings prove Fe3O4/GO/PVP as an inexpensive and efficient adsorbent for removal of cationic dyes.

A comparative study of single and bi-doped Co3O4 nanocatalysts for the photodegradation of methyl orange dye

In this work, pure Co3O4, Ni-, CuNi-, and CdNi-doped Co3O4 nanoparticles (NPs) were prepared via chemical co-precipitation method. The obtained Co3O4 exhibits a cubic crystalline structure with an average crystallite size of ∼19.9 nm, according to the XRD profiles. Moreover, the effects of Ni-, CuNi- and CdNi-doped Co3O4 on the crystallite size, band gap, and magnetic properties of the cubic Co3O4 were considered. It was observed that the crystallite sizes and the magnetic properties of Ni(0.1)Co3O4(0.9) and Cu(0.05)Ni(0.05)Co3O4(0.9) samples are smaller, while the optical band gaps are wider than that of pure Co3O4. The Cd(0.05)Ni(0.05)Co3O4(0.9) sample has a higher magnetic properties in comparison to the other samples. The elemental composition of the produced Co3O4, Ni-, CuNi- and CdNi-doped Co3O4 NPs is determined using the EDX technique. A morphological study by TEM showed that the CdNi-doped Co3O4 sample has semi-spherical particles with an average particle diameter of ∼70.4 nm. The photodegradation of methyl orange (MO) dye in aqueous solution under visible light irradiation was used to examine the catalytic activity of pure and doped Co3O4 NPs. The results showed that the degradation of MO dye was improved in the doped samples and takes the following order: Cd(0.05)Ni(0.05)Co3O4(0.9) (∼93%) > Cu(0.05)Ni(0.05)Co3O4(0.9) (∼85%) > Ni(0.1)Co3O4(0.9) (∼79.7%) > pure Co3O4 (∼64.4%) in 120 min of irradiation time. The pseudo-first-order reaction rate constant for Cd(0.05)Ni(0.05)Co3O4(0.9) is equal to 0.021 min−1, which is about 1.6-times increased in compared to pure Co3O4. The improved photocatalytic efficiency of this sample was attributed to an extrinsic defect generated by CdNi doping, small particle sized and high surface area, which delayed the electron/hole recombination and caused appropriate band gap configuration.

Gum arabic/guar gum based biopolymeric nanohydrogel for shelf-life enhancement of grapes and photocatalytic dye reduction

Recently, natural food preservation systems composed of metal oxide nanoparticles (NPs) gained great attention from the food manufacturers, however, toxicity of NPs is a major concern. Therefore, in this study we synthesized multifunctional gum arabic/guar gum biopolymeric nanohydrogel embedded with NPs for the enhancement of the shelf-life of the grapes and for photocatalytic dye reduction. Copper, zinc, and iron metal oxide NPs were tailored using chemical precipitation and co-precipitation methods and subjected to various characterization processes. The smaller particle size was observed with iron oxide NPs (23.64 nm) as compared to other NPs (Cu and Zn). All metal oxide NPs showed cell viability ranging from 90.73 – 99.94%. The average droplet size of the formulated hydrogel samples was ranging from 240.6 to 345.8 nm with an irregular and rough morphology. Nanohydrogels at varied concentrations embedded with metal oxide NPs showed cell viability in the range of 93.73–99.97%. Zinc metal oxide NPs embedded in hydrogel showed higher spreadability properties, while hydrogel embedded with iron oxide NPs showed lower spreadability properties. Grapes coated with formulated hydrogel did not affect the physicochemical attributes during the storage (10 days), hence it can be scaled up as an effective natural preservation system.

Sr2+ and Co2+ Co-Doped LaAlO3 Leads to Synergistic Enhancement of Electric Heating and Infrared Radiation Abilities for MEMS Light Source Application

The MEMS infrared light source is one of the core components of the NDIR gas sensor, and its thermal stability, emissivity, and modulation characteristics all have a crucial impact on the accuracy and sensitivity of the entire device for gas detection. This paper provides a detailed analysis of the structure and working principle of MEMS light source chips, and starting from the idea of multi-functional materials, proposes a new MEMS infrared light source chip design concept for achieving high efficiency the electric heating and thermal to light conversions simultaneously by a monolayer of multi-functional material. Based on this concept, La0.7Sr0.3Al0.5Co0.5O3 material was successfully prepared used a chemical co-precipitation method and confirmed by XRD. By doping the Sr2+ and Co2+ at the A and B sites of LaAlO3 material separately, the approximately insulating LaAlO3 material has a certain degree of conductivity and electric heating ability. Moreover, the co-doping of Sr2+ and Co2+ also makes LaAlO3 material exhibit excellent infrared radiation ability in the range of 2.5–25 μm. Based on lattice structure of La0.7Sr0.3Al0.5Co0.5O3 and SEM research, the principle of enhancing conductivity and emissivity has been analyzed in detail.

Facile fabrication of copper oxide modified sensor for determination of Mycophenolate mofetil in biological fluids: A cyclic voltammetric study

In the present work, the copper oxide nanoparticles (CuO Nps) was synthesized via chemical co-precipitation method for the detection of Mycophenolate mofetil (MMF). The synthesized Nps were characterised using traditional techniques namely X-ray diffraction (XRD), Scanning electron microscopy (SEM) and EDAX studies which showed better crystallinity with particle size of around 26 nm. The physiological pH of 7.4 was maintained throughout the studies. CuO Nps fabricated carbon paste electrode (CuO/FCPE) showed a considerable electroactive surface area with contrast to BCPE and showed better sensitivity and stable current responses. Further various other studies such as sweep rate, concentration, pH studies were carried out which showed lower LOQ and LOD i.e. 0.5 and 0.15 μM respectively. The developed electrode showed greater stability around 94% by retaining its activity. The fabricated electrode further studied for practical analysis of MMF in human urine trial which showed greater recovery of MMF in range of 96%–99%.

β-Cyclodextrin-Functionalized Fe3O4-Supported Pd-Nanocatalyst for the Reduction of Nitroarenes in Water at Mild Conditions.

In this study, a novel heterogeneous catalyst (Fe3O4@β-CD@Pd) has been developed by the deposition of palladium nanoparticles on the β-cyclodextrin-functionalized surface of magnetic Fe3O4. The catalyst was prepared by a simple chemical co-precipitation method and characterized extensively by using Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma-optical emission spectrometry (ICP-OES) analyses. Herein, the applicability of the prepared material was evaluated for the catalytic reduction of environmentally toxic nitroarenes to the corresponding anilines. The catalyst Fe3O4@β-CD@Pd showed excellent efficiency for the reduction of nitroarenes in water under mild conditions. A low catalyst loading of 0.3 mol % Pd is found to be efficient for reducing nitroarenes in excellent to good (99-95%) yields along with high TON values (up to 330). Nevertheless, the catalyst was recycled and reused up to the 5th cycle of reduction of nitroarene without any loss of significant catalytic activity.

Development and antibacterial investigation of Linezolid loaded SPIONs and HPLC method development for quantitative analysis of Linezolid.

Linezolid (LNZ) is extremely prone to resistance. The development of resistance to LNZ should be taken into consideration when selecting this drug as a therapeutic option. By considering the hypothesis that reactive oxygen species (ROS) generated by iron oxide nanoparticles (MNPs) could kill the infecting bacteria. So, we hypothesized the synergistic antibacterial effect of iron oxide nanoparticles and LNZ. To study the release and antibacterial effects of LNZ loaded superparamagnetic iron oxide nanoparticles (SPIONs) on Staphylococcus aureus and Streptococcus pneumoniae. Ferrofluid containing SPIONs was synthesized via chemical co-precipitation method and stabilized by sodium lauryl sulphate (SLS). SPIONs were then loaded with LNZ and characterized for particle size, FT-IR, XRD, and entrapment efficiency. Further antibacterial activity of SPIONs and LNZ-loaded SPIONs was investigated. For the in-vitro release findings, a HPLC analytical method development and validation was performed. Isolation of LNZ was accomplished on a C-18 column with methanol: TBHS (Tetra butyl ammonium hydrogen sulphate, 50:50 v/v). The eluate was monitored at 247 nm with retention time of 4.175 min. The MNP's DLS measurement revealed monodispersed particles with an average size of 16.81 ± 1.07 nm and PDI 0.176 ± 0.012. In optimized formulation, 25 ± 1.75% (w/w) of the drug was found to be entrapped. XRD revealed uniform coating of oleic acid covering the entire magnetic particles surface with no change in its crystallinity. An effective antimicrobial activity was observed at the lowered dose of drug. A robust HPLC method was developed to quantify the LNZ in MNPs and outcomes showed that the reduced dose of LNZ incorporated in SPIONs was able to show similar activity as the marketed product. Successfully reduction of dose of LNZ was established with the aid of biocompatible MNPs to attain the equivalent antibacterial activity.