Elemental Mapping Techniques Research Articles

Synthesis of Sm‐TADDbBP@MCM‐41 as a Robust, Reusable, and Practical Nanocatalyst in the Homoselective [2 + 3] Cycloaddition Reaction

ABSTRACTSchiff‐base materials are known ligands for the coordination of metal ions and the synthesis of various stable and useful complexes. Therefore, herein, a novel Schiff‐base compound {2,2′‐((1E,11E)‐2,5,8,11‐tetra azadodeca‐1,11‐diene‐1,12‐diyl) bis (4‐bromophenol)} was introduced that formed from condensation of triethylenetetramine (TETA) and 5‐bromo‐2‐hydroxybenzaldehyde (5B2HB). This Schiff‐base ligand was labeled as TADDbBP. Besides, mesoporous MCM‐41 was synthesized using tetraethyl orthosilicate (TEOS), hydrolyzing cetyltrimethylammonium bromide (CTAB) and NaOH solution (2 M), followed by calcination at 550 °C, and further, the silanol sites on the MCM‐41's surface were modified by 3‐chloropropyltriethoxysilane (3Cl‐PTES), which modified MCM‐41 was labeled as 3‐Cl‐Pr@MCM‐41. In the next step, the synthesized TADDbBP (as Schiff‐base ligand) was grafted on 3‐Cl‐Pr@MCM‐41, which was labeled as TADDbBP@MCM‐41, and further, it was coordinated with samarium ions (which was labeled as Sm‐TADDbBP@MCM‐41 nanocatalyst) using Sm (CH3COO)3. This is the first report on the production of Sm‐TADDbBP@MCM‐41 nanocatalyst, this nanocatalyst was characterized by TEM, SEM, EDX, elemental mapping, BET method, ICP, XRD, and TGA techniques. In the final step, the catalytic performance of Sm‐TADDbBP@MCM‐41 nanocatalyst has been checked in the homo‐selective producing of tetrazoles through [2 + 3] cycloaddition of benzonitriles and sodium azide (NaN3) in PEG‐400 as available, nontoxic, green, and safe solvent. This nanocatalyst provides excellent selectivity in the synthesis of tetrazoles. In addition, Sm‐TADDbBP@MCM‐41 nanocatalyst can be separated and recycled for several cycles without significant reactivation or metal leaching.

Effect of gamma irradiation on properties of the synthesized PANI-Cu nanoparticles assimilated into PS polymer for electromagnetic interference shielding application

Conductive polymer nanocomposites for electromagnetic interference (EMI) shielding are important materials that can be combat the increasingly dangerous radiation pollution arising from electronic equipment and our surrounding environment. In this work, we have synthesized polyaniline-copper nanoparticles (PANI-Cu NPs) by the copper salt based oxidative polymerization method at room temperature and then added with different concentration (0, 1, 3 and 5 wt%) in polystyrene polymer forming PS/ PANI-Cu nanocomposites films by means of the traditional solution casting technique. The formed PANI-Cu NPs were investigated by UV/Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and SEM/EDX elemental mapping techniques. On the other hand, the prepared PS/PANI-Cu nanocomposites films were evaluated by UV and SEM, the mechanical properties of the nanocomposites films were evaluated and showed an improvement by added PANI-Cu NPs up to 3 wt% and 50 kGy gamma exposure dose. The PS/PANI-Cu nanocomposites films were examined as electromagnetic interference shielding material. Electromagnetic shielding effectiveness of the produced nanocomposites were tested in the X-band of the radio frequency range namely from 8 to 12 GHz using the vector network analyzer (VNA) and a proper wave guide. All samples were studied before and after 50 kGy gamma-ray irradiation under the same condition of pressure and temperature. The results showed that the nanocomposites have improved shielding properties.

Biosynthesis of gold nanoparticles by using gelatin as reducing and stabilizing agent under ultrasound irradiation: Application of its catalytic activity and for ameliorating motor recovery after spinal cord injury in the Wistar rat’s model

The current project describes the facile preparation of Au nanoparticles mediated by gelatin as a natural capping and reducing agent in mild condition. The formation of Au nanoparticles stabilized by gelatin (Au NPs/Gelatin) and structural characteristics were studied via UV–Vis, FT-IR, TEM, FE-SEM, EDX and elemental mapping techniques. The evidence shown that gelatin-capped gold nanoparticles resulted in the lowest average particle sizes of 15–25 nm and spherical shapes nanoparticles. Further, newly synthesized Au NPs/Gelatin are used as a nanocatalyst for the reduction of 4-nitrophenol (4-NP) dyes. A UV–Vis spectrophotometer is employed to track the effectiveness of the reduction process. Recyclability in six further degradation cycles is used to assess the sustainability of this catalyst, and the results show a steady and notable degradation activity. In the in vivo experiment, 60 male rats were classified into four groups: control, intact, sham, and Au NPs/Gelatin nanocatalyst (20 µg/kg) groups. The Hematoxylin and eosin staining was conducted to examine the post-injury lesions. Additionally, somatosensory evoked potential experiments were conducted to assess the recovery of neural conduction. The expression of GFAP was evaluated to determine the extent of astrogliosis. Furthermore, the behavioral outcomes of the rats were evaluated using the BBB scores on a weekly basis after the spinal cord injury onset. The results of the research demonstrated that the neuroprotective effects of Au NPs/Gelatin nanocatalyst led to an amelioration in the rat’s model. Electromyography (EMG) data revealed a remarkable amelioration in hindlimb function in the Au NPs/Gelatin nanocatalyst (20 µg/kg) group. The ventral motor neurons number significantly raised, while the cavity areas significantly decreased in the Au NPs/Gelatin group. Moreover, the expression of GFAP was notably reduced in the Au NPs/Gelatin nanocatalyst group. The Au NPs/Gelatin nanocatalyst group exhibited a significant reduction in delayed responses and a significant increase in BBB scores during sensory tests.

Sustainable synthesis of Au nanoparticles templated over chitosan/pectin hydrogel for the treatment of gastric cancer

This report demonstrates the sustainable synthesis of hybrid biopolymer hydrogel supported Au NPs followed by its characterizations and biological explorations. The chitosan/pectin (CS-Pec) composite hydrogel was used as the support. The biopolymers might function as an eco-friendly reductant for the Au3+ ions over and above encapsulating stabilizer of the Au NPs by exploiting their electron rich organo-functions. UV–Vis, SEM, TEM, EDX, elemental mapping and XRD techniques were engaged to appraise the physicochemical features of the material. Subsequently, the material (Au NPs@CS-Pec) was subjected to diverse biological applications and following the course it showed high antioxidant activities against DPPH free radical. The related IC50 of the antioxidant material against DPPH found as 139 µg/mL. Towards the oncological investigation, it was used against the gastric cancer cell lines (AGS and KATO III) and the corresponding IC50 values were 225.3 and 341.5 µg/mL respectively. The outcome justifies that the produced NPs have successfully inhibited the proliferation of gastric cancer cells, and those are mostly eliminated at a high dose of the NPs.

A highly selective and sensitive trimethoprim sensor based on surface molecularly imprinted nanocavities coordinated polydopamine/gold nanorods-functionalized acupuncture needle microelectrode

Excessive amount of antibiotics have serious detrimental effects on the environment, making precise monitoring and removal increasingly crucial. Trimethoprim (TMP) is a typical kind of antibiotic. Herein, a novel microdetector was fabricated on the matrix of acupuncture needle (AN). The functional interface was constructed using a green electrosynthesis method, incorporating three-dimensional coral-like gold nanorods (3D-CAuNRs), polydopamine (pDA), polypyrole (pPY) and TMP molecules. Characterization was performed using electrochemistry, high-resolution SEM and elemental mapping techniques. Notably, nanocavities were formed through electropolymeric molecular imprinting, resulting in highly selective and sensitive detecting of TMP. This was attributed to the structure-complementary and configuration-suitable microenvironment, facilitating specific electron-transfer. The intrinsic properties of the microsensor were thoroughly investigated. Under optimized conditions, the sensor exhibited a wide linear range of 0.05 ∼ 50 µmol/L with a low limit detection of 0.017 µmol/L (S/N = 3) for TMP, along with high selectivity, reproducibility, and stability. Furthermore, the sensor demonstrated applicability for detecting TMP in environmental water, soil and cefalexin and trimethoprim capsules.

Sulfonated magnetic spirulina nanobiomaterial as a novel and environmentally friendly catalyst for the synthesis of dihydroquinazolin-4(1H)-ones in aqueous medium

Spirulina algae is an excellent candidate for catalyst preparation due to its reactive functional groups, cost-effectiveness, widespread commercial accessibility, and biodegradability. In this study, magnetized Spirulina was used for the synthesis of dihydroquinazolin-4(1H)-ones (DHQZs) as catalyst. Magnetized Spirulina was produced by CoFe2O4 and sulfonation method using chlorosulfonic acid to create the catalyst [CoFe2O4-Sp-SO3H]. It was affirmed by various techniques, including Fourier transform infrared (FT-IR), Vibrating sample magnetometry (VSM), Powder X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS), Thermogravimetric analysis (TGA), Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FE-SEM), and elemental mapping techniques. DHQZs synthesis was accomplished through a concise one-pot, three-component reaction involving a range of diverse aldehydes, isatoic anhydride, and primary aromatic amine, within an aqueous medium. The method offers several advantages, including using green conditions, the generation of several new 2-furan-quinazolinone derivatives, chromatography-free purification, short reaction times, appropriate yield of product (75–96%), and catalyst recyclability. The proposed catalyst and water as solvent demonstrated a strong synergistic effect, leading to the prosperous synthesis of various novel dihydroquinazolinones at 60 °C. These numerous benefits make our approach highly attractive for academic research and industrial applications.

Optimization of culture conditions of Scenedesmus sp. algae and catalytic performance of a NiFe2O4@SiO2/MgO magnetic nano-catalyst for biodiesel production.

This study aims to optimize the lipid content of Scenedesmus sp. for high-yield biodiesel production. Three factors affecting the culture conditions, namely salinity, nitrogen concentration, and light intensity, were selected and their effects on the maximum lipid content were investigated using the Box Behnken design. The results showed that the maximum lipid content (32.7% of algal dry weight) was obtained in the algal samples cultured under the optimized conditions. A core-shell magnetic nano-catalyst, NiFe2O4@SiO2/MgO, was synthesized and used to produce biodiesel via the transesterification reaction. The nano-catalyst was characterized by field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffraction analysis (XRD), vibrating sample magnetometry (VSM), elemental mapping techniques, transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). Using the Box Behnken design and keeping the temperature constant, the molar ratio of methanol to oil, the amount of catalyst, and the time were optimized to achieve the maximum yield of biodiesel. The maximum yield of biodiesel was 95.3% under the optimal conditions.

Design, preparation and characterization of magnetic nanoparticles functionalized with chitosan/Schiff base and their use as a reusable nanocatalyst for the green synthesis of 1H-isochromenes under mild conditions.

In this study, a Schiff base complex magnetic nanocatalyst was designed and prepared. The structure of the Fe3O4@CS-SB-CaMgFe2O4 nanocatalyst was characterized using FT-IR spectroscopy, XRD, VSM, FE-SEM, EDX, elemental mapping, BET, and TGA techniques. The synthesis of 1H-isochromene compounds has attracted the attention of chemists due to their biological and medicinal properties. The 1H-isochromene derivatives were synthesized in the presence of the Fe3O4@CS-SB-CaMgFe2O4 nanocatalyst with excellent efficiency and short reaction time as well as according to the rules of green chemistry. This reaction was carried out using Fe3O4@CS-SB-CaMgFe2O4 as a catalyst to develop a simple method with low activation energy at room temperature under optimal conditions. This catalyst provides a promising route for the synthesis of 1H-isochromene multiple times through its recyclability without significant loss of catalytic activity. This nanocatalyst possesses several advantages, including cost-effectiveness, facile separation, environmental friendliness, and recyclability, for the efficient production of 1H-isochromenes. The obtained compounds were further analyzed using spectroscopic techniques, such as melting point, FT-IR, 1H NMR, and 13C NMR analyses, to confirm their structures. The spectra of the synthesized compounds were recorded and analyzed, and a plausible mechanism for their synthesis was proposed. The characterization results and structural elucidation provide valuable insights into the preparation of these compounds.

Nanomagnetic CoFe2O4@SiO2-EA-H3PO4 as a zwitterionic catalyst for the synthesis of bioactive pyrazolopyranopyrimidines and dihydropyrano[2,3-c]pyrazoles.

This study presents the development of a phosphoric acid-based zwitterionic catalyst immobilized on CoFe2O4 nanoparticles [CoFe2O4@SiO2-EA-H3PO4]. The structure of the nanocatalyst CoFe2O4@SiO2-EA-H3PO4 was identified by applying several spectroscopic techniques, i.e. FT-IR, SEM, TEM, XRD, EDX, elemental Mapping, VSM, TGA, and BET techniques. The catalytic efficiency of CoFe2O4@SiO2-EA-H3PO4 was evaluated in the water-based multicomponent synthesis of pyrazolopyranopyrimidine and dihydropyrano[2,3-c]pyrazole derivatives. Subsequently, an exploration of the antibacterial properties of the compounds was conducted. The catalytic system offers several advantages, encompassing high efficiency, brief reaction duration, uncomplicated operation, and facile recycling of the catalyst.

Sodium alginate-modified alkali-activated eggshell/Fe3O4 nanoparticles: A magnetic bio-based spherical adsorbent for cationic dyes adsorption

Herein, a mixture of eggshell (ES) and magnetite nanoparticles (MNPs) was alkali-activated using NaOH/Na2SiO3 solution and then, impregnated with sodium alginate (SA) to prepare a magnetic bio-based adsorbent (namely SAAES/SA/MNPs) for the decontamination of water containing basic dyes, in particular, methylene blue (MB) and crystal violet (CV). The physicochemical properties of magnetic spheres of SAAES/SA/MNPs were characterized using XRD, FTIR, FESEM, EDX, elemental mapping, TEM, and zeta potential techniques. Dye adsorption equilibrium was studied experimentally at pH 8.0 and 25–55 °C, and a statistical physics multilayer model was applied to understand the removal mechanism of these dyes including the adsorption orientations on the adsorbent surface. The number of adsorbed dye molecules per functional group (n) of this bio-based adsorbent ranged from 0.70 to 0.91, indicating the presence of vertical and horizontal adsorption orientations for these organic molecules at all tested solution temperatures. The calculated saturation adsorption capacities (Qsat) were 332.57–256.62 mg/g for CV and 304.47–240.62 mg/g for MB, and an exothermic adsorption was observed for both adsorbates. The estimated adsorption energies (∆E) were < 25 kJ/mol, confirming that the SAAES/SA/MNPs–dye interactions were governed by physical forces as electrostatic interactions. This bio-based adsorbent was effectively regenerated using ethanol and it can be reused showing a removal of 71 and 74 % of MB and CV, respectively, after fourth adsorption–desorption cycles. Overall, the results of this article suggest the attractive performance of SAAES/SA/MNPs for removing basic dyes from aqueous solutions, thus highlighting the promising potential of this magnetic bio-based adsorbent for sustainable wastewater treatment at an industrial level.

Investigation of microbial fuel cell performance based on the nickel thin film modified electrodes

Microbial fuel cells (MFCs) are a self-sustaining and environmentally friendly system for the simultaneous was tewater treatment and bioelectricity generation. The type and material of the electrode are critical factors that can influence the efficiency of this treatment process. In this study, graphite plates and carbon felt were modified through the electrodeposition of nickel followed by the formation of a biofilm, resulting in conductive bio-anode thin film electrodes with enhanced power generation capacity. The structural and morphological properties of the electrode surfaces were characterized using X-ray diffraction, energy-dispersive X-ray spectroscopy, elemental mapping, and field-emission scanning electron microscopy techniques. Maximum voltage, current density, and power generation were investigated using a dual-chamber MFC equipped with a Nafion 117 membrane and bio-nickel-doped carbon felt (bio-Ni@CF) and bio-nickel-doped graphite plate (bio-Ni@GP) electrodes under constant temperature conditions. The polarization and power curves obtained using different anode electrodes revealed that the maximum voltage, power and current density achieved with the bio-Ni@CF electrode were 468.0 mV, 130.72 mW/m2 and 760.0 mA/m2 respectively. Moreover, the modified electrodes demonstrated appropriate stability and resistance during successful runs. These results suggest that nickel-doped carbon-based electrodes can serve as suitable and stable supported catalysts and conductors for improving efficiency and increasing power generation in MFCs.

Electrospinning of photochromic poly(ethylene terephthalate) nanofibers toward information authentication.

The use of photochromism to enhance the anti-counterfeiting of a wide range of economic goods is an intriguing prospect. Creating a translucent anti-counterfeiting nanocomposite is critical to improving the engineering procedures of the encoding materials. Herein, we use electrospinning to produce anti-counterfeiting nanofibrous films from nanoparticles of rare-earth aluminate (NREA) and recycled poly(ethylene terephthalate) (PET). Different nanofiber films with distinct emission properties were created using different ratios of NREA. The ultraviolet (UV)-induced photochromism of the NREA@PET nanofibers was proved. Immobilizing NREA at the nanoscale ensures better dispersion without agglomeration in the PET nanofibrous matrix, which is essential for the development of transparent NREA@PET films. Diameters of 4-13 nm for NREA were shown using transmission electron microscopy. X-ray fluorescence spectroscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, elemental mapping, and other techniques were used to investigate the photochromic nanofibers' morphology, elemental contents, optical transmittance, and mechanical performance. It was observed that the nanofiber diameter in NREA@PET was between 150 and 250 nm. Excitation and emission bands of electrospun NREA@PET nanofibrous films were monitored at 365 and 518 nm, respectively. The superhydrophobicity of NREA@PET increased with increasing NREA concentration. The transparent nanofibers exhibited fast and reversible dual-mode fluorescent photochromism to green emission without fatigue when stimulated beneath a UV source. Using the present anti-counterfeiting films can be regarded as a simple technique to develop flexible materials to launch an ideal marketplace with affordable societal and economic advantages.

Synthesis and Characterization of Core-Shell Mesoporous Iron oxide Magnetic Nanoparticles using Modified Co-Precipitation Method

In recent era, development of nanotechnology is an art of delivery of drug by improving its compatibility, effectiveness and efficacy. Among all nanoparticles, magnetic nanoparticles play a predominant role to shows their targeted drug delivery using a magnetic field, also helps to diagnose the diseases like cancer. The present study included preparation of four different mesoporous nanoparticles using the Pluronic block copolymer P123 as a surfactant template, then insert iron oxides using co-precipitation method. The resulted formed mesoporous magnetic nanoparticles are examined for structural characters by using FTIR, XRD, HRSEM and Elemental Mapping techniques. The results of X-ray diffraction (XRD) showed that the formed composites conserved ordered mesoporous structure after the formation of iron oxide nanoparticles in the pores. FTIR results indicated that the surface contains silanol group and Fe–O on the surface of the materials at 1060 cm-1 and 1020 cm-1 peaks respectively. Scanning electron microscopy (SEM) results showed that all mesoporous magnetic nanoparticles within the range of size from 50 to 100nm also possessed a regular spherical shape. These particles possessed high surface area, high pore volume and showed magnetic response sufficient for drug targeting in the presence of an external magnetic field. Elemental mapping data indicated about the percentage of all elements present in the mesoporous materials. We concluded that all four types of magnetic nanoparticles are structurally arranged in their structure with sufficient percentage of elements on their particle surface along with good size range. Further loading of drug into all types of magnetic nanoparticles decides the loading efficiency, stability and drug release nature.

Facile synthesis and characterization of polymer composites with cobalt ferrite and biomass based activated carbon for microwave absorption

In this work, flexible EMI shield materials have been prepared by the solution cast technique using AC-STG {activated carbon derived from Sal tree's gum}, CoFe2O4 nanoparticles and a polymer electrolyte {P(VDF-TrFE) + 15 wt% LiTFSI + 50 wt% EMIMTFSI}. The prepared polymer composites have been characterized for structural, morphological, thermal, ionic conductivity, dielectric, and magnetic properties. EMI shielding effectiveness has been obtained in the X-band (8.2–12.4 GHz). AC-STG particles have been characterized using XRD, FESEM EDX with elemental mapping, FTIR and RAMAN techniques. The CoFe2O4 (CF) nanoparticles have been prepared using the hydrothermal method. The highest ionic conductivity of ∼ 3.24х10−3 S.cm−1 for polymer electrolyte (PE15IL50) has been obtained at room temperature. On addition of AC-STG and CF particles to the polymer electrolyte, enhanced EMI shielding effectiveness and thermal stability of the composite films has been achieved. Also, FTIR results give the confirmation of interaction between the polymer electrolyte, AC-STG and CF particles. This study demonstrates that the EMI shielding properties of the polymer composite (PE15IL50AC-STG4CF5) get improved owing to the synergy between the properties of AC-STG and CF nanoparticles resulting in EMI shielding of ∼ 49.6 dB at 8.2 GHz (absorption ∼ 99.99%). There are three factors, viz., dielectric losses, magnetic losses and interfacial polarization which contribute majorly to this much desirable EMI performance. The studies being reported indicate PE15IL50AC-STG4CF5 polymer composite to be an excellent biomass-based composite for EM wave absorption.

Cation-heterogeneity in internally gelated U1-zCezO2-x, 0.15 ≤ z ≤ 0.3 microspheres

Internal gelation of aqueous mixtures of metal (M = Ln, An) nitrate with Uranyl Nitrate is generally assumed to yield cation homogeneity and a fluorite type single phase U1-zMzO2±x solid solution. As-sintered (U,Ce)O2 internally gelated microspheres, manufactured with target z values up to 0.3 using Ce(NO3)3, were observed to exhibit systematic peak broadening and splitting at higher 2θ angles in their X-Ray diffraction (XRD) patterns, correlating with increasing z≥0.15. This was interpreted as an unexpected departure from a single phase material. Thermogravimetry was used to make an initial assessment whether these peak anomalies were caused by an oxygen hypostoichiometry. Results indicated global oxygen stoichiometry for all compositions. The subsequent detailed characterization study via Electron Probe Micro Analysis of cross-sections of the as-sintered microspheres revealed the systematic presence of spherical Ce concentration gradients, as well as µm-sized highly Ce-enriched features. EDS and TEM studies on focused ion beam lamellae extracted from the cross-sections of as-sintered microspheres revealed a hexagonal Ce4.67(SiO4)3O minor phase manifesting as single grain precipitates and clusters uncovering the presence and critical role of Silicon as an unexpected contaminant and Ce-scavenger from surrounding (U,Ce)O2 grains. Characterization at intermediate heat treatment steps revealed that the systematic U/Ce heterogeneity features are already present post-gelation and are independent of the superimposed trace Ce-Si-O phase. This work constitutes the first systematic cation distribution study on cross-sections of (U,Ce)O2±x microspheres, executed on a series of compositions, using a combination of elemental mapping techniques.

Development of a novel green catalyzed nanostructured Cu(II) macrocyclic complex-based disposable electrochemical sensor for sensitive detection of bisphenol A in environmental samples

BPA is an endocrine disruptor and the leading environmental pollutant due to its use as raw material in industries. Therefore, the present work reports the sensitive, efficient, and disposable electrochemical paper-based SPE for determining the BPA sensor using an amide-based macrocyclic complex (nanostructured complex of copper acetate with macrocyclic ligand, i.e., CuL (CH3COO)2) synthesized using Citrus limon (lemon) extract via sonication for the first time. The structural, morphological, and electrochemical analyses have been characterized by mass spectroscopy, FTIR, UV–Vis, XRD, FESEM-EDX, elemental mapping and electrochemical techniques. The sensor platform for detecting BPA was fabricated by simple drop-casting on the disposable paper-based SPE using macrocyclic complex, i.e., CuL (CH3COO)2/SPE. After optimizing the conditions, CuL (CH3COO)2/SPE electrode was employed for determining BPA via CV with a wide linear range of 31 × 10−9 μM–0.205 μM, low LOD of 0.027 nM, and high sensitivity of 49.71 μA (log nM)−1 cm−2 having correlation coefficient (R2) of 0.976 which is quite better in compared to other reported SPE sensor for detection of BPA. Further, our sensor also showed good selectivity and reproducibility, in addition to detecting BPA in environmental samples (tube well water, river water and drain water) with acceptable recoveries and RSDs values. In this work, the combination of macrocyclic complex and paper-based SPE has turned out to be a cost-effective electrochemical sensor.

Pvp-based deep eutectic solvent polymer: Sustainable Brønsted-Lewis acidic catalyst in the synthesis of α-aminophosphonate and bisindole

Polymeric deep eutectic solvents (PDESs) have emerged for augmentation of the functions of deep eutectic solvents (DESs) as a sustainable material class. Considering the common synthetic limitation of PDESs to the in-situ polymerization of deep eutectic monomers, herein, we have implemented linear polyvinylpyrrolidone (PVP) to develop a simple-to-prepare, atom-economical, cost-effective, and eco-friendly Brønsted-Lewis acidic PDES via ZnCl2 and a quaternization procedure. The prepared PDES was characterized by SEM, EDS, elemental mapping, FT-IR, and TGA techniques. This method enables physicochemical tunation of the PDES by altering the molar ratio of ZnCl2 to PVP monomer repeating units. The PDES was used as a heterogeneous catalyst to promote greener approaches towards biologically significant scaffolds via a multicomponent reaction of aldehydes, amines, and tri(alkyl/aryl)phosphites to synthesize secondary and tertiary α-aminophosphonates (APs), in addition to a carbon–carbon bond-forming reaction to synthesizing bis(indolyl)methanes (BIMs) from aldehydes and indolyl compounds. PDESs proved to be highly efficient catalysts for these transformations, providing mild and high-yielding green protocols for an extensive library of both APs and BIMs. The desired compounds from either transformation group were obtained shortly with good to excellent yields (15–120 min for APs and 100–200 min for BIMs). Examination with BIMs revealed that the protocol is amenable to large-scale production without significant loss of efficiency. In addition, the stability of the PDES catalyst was confirmed from five successful recycles, in which no significant decrease in the activity was monitored.

Nickel ferrite nanoparticles doped on hollow carbon microspheres as a novel reusable catalyst for synthesis of N-substituted pyrrole derivatives

Pyrroles are widely spread worldwide because of their critical applications, especially pharmacology. An expedition method for one-pot synthesis of N-substituted pyrrole derivatives has been presented by a reaction between 2,5-dimethoxytetrahydrofuran and various primary aromatic amines in the presence of NiFe2O4 anchored to modified carbon hollow microspheres (NiFe2O4@MCHMs) as a recoverable reactive catalyst. The Classon-Kass method has been used to synthesize the pyrroles in excellent yields and short reaction times in the same direction with green chemistry rules. This reaction was carried out by employing NiFe2O4@MCHMs as a catalyst to make a simple procedure with short activation energy in water as an accessible, non-toxic, and biodegradable solvent. This catalyst provides a promising pathway to synthesize N-substituted pyrroles several times in a row through the recyclability without remarkable loss of its catalytic activity. The NiFe2O4@MCHMs nanocatalyst was characterized by applying FT-IR, XRD, FE-SEM, TEM, EDS, BET, TGA, VSM, and elemental mapping techniques. Also, the synthesized N-substituted pyrrole derivatives were identified using melting point, FT-IR, and 1H NMR analyses.

ZnO nanoflowers modified pencil graphite electrode for voltammetric DNA detection and investigation of Gemcitabine–DNA interaction

In this study, ZnO nanoflowers (ZnONFs) were synthesized using sonochemical method, which is a simple, environmentally friendly, low-cost and rapid method. ZnONFs was characterized by using FE-SEM, EDS, elemental mapping, FTIR and XRD techniques. Single use pencil graphite electrode (PGE) modified with ZnONFs was characterized using FE-SEM, EDS, elemental mapping, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods. This developed electrode was used for the first time for the determination of calf thymus double-stranded DNA (dsDNA) and the chemotherapeutic drug Gemcitabine (GEM) using differential pulse voltammetry (DPV). The detection limits (DLs) of dsDNA and GEM were calculated as 1.91 μg/mL and 2.47 μg/mL, respectively. The interaction of GEM and dsDNA at different times was investigated by measuring the changes in both GEM and guanine oxidation signals by DPV technique. The developed nanoflower-based biosensor responded in as short as 5 min in the DNA-anticancer drug interaction study. The study provides advantages such as low cost, biocompatibility, and easy synthesis of the used nanomaterial synthesis, as well as low detection limit and short interaction time at the sensor stage.

Development of doxorubicin-encapsulated magnetic liposome@PEG for treatment of breast cancer in BALB/c mice.

The magnetic doxorubicin-encapsulated liposome/PEG/Fe3O4 (called as DOX@m-Lip/PEG) was synthesized and studied as a novel nanocarrier for the treatment of breast cancer in BALB/c mice. Nanocarrier was characterized by FT-IR, zeta-potential sizer, EDX elemental analysis, EDX mapping, TEM, and DLS techniques. The results showed that the size of the nanocarrier was determined around 128nm by TEM. EDX study confirmed PEG-conjugation in the magnetic liposomes and was homogenously distributed in the nanosize range (100-200nm) with a negative surface charge (-61.7mV). The kinetic studies indicated that the release of doxorubicin from DOX@m-Lip/PEG follows the Korsmeyer-Peppas model. The n-value of the model was 0.315, indicating that doxorubicin release from the nanocarrier had a slow releasing rate and followed Fick's law. The DOX release from the nanocarrier lasted a long time (more than 300h). In in vivo part, a mouse 4T1 breast tumor model was used. The in vivo results indicated that DOX@m-Lip/PEG caused much stronger tumor cell necrosis and less cardiotoxic effects than the other groups. In conclusion, we show that m-Lip/PEG is a promising nanocarrier for low dosage and slow release of doxorubicin in treating breast cancer, and treatment with encapsulated DOX (DOX@m-Lip/PEG) demonstrated higher efficacy with low cardiac toxicity. Besides, the magnetic property of m-Lip@PEG nanocarrier allows it to be a potent mater for hyperthermia and MRI studies.