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Two new amphiphilic ionic liquids (AILs) were synthesized through the opening reaction of the epoxy ring of glycidyl 4-nonylphenyl ether (GNE) using ethanol amine (EA), followed by quaternization u...

Rutile phase of titanium oxide and platinum nanoparticle decorated rutile titania is prepared by a surfactant free hydrothermal process in acidic condition. The pure rutile phase of TiO2 particle is forms the specific cauliflower morphology. Hydrothermal process in presence of specific acid addition led to the formation of cauli-flower shaped rutile phase of titania. The efficiency and solar assisted photo catalytic ability of these materials are tested for methylene blue degradation as well as hydrogen generation by methanol reforming process. The X-ray diffraction of pattern of pure rutile phase formation is confirmed by reported JCPDS data. The surface physico-chemical property of prepared rutile Titania is further characterized by BET, Raman and SEM analysis. The HR-TEM of the prepared samples show the reduced particle size for rutile titania and studied their morphology in detail. Solar light assisted methylene blue degradation reaction was carrying out to study the catalytic efficiency towards dye degradation and kinetic activity of the same for prepared commercial titania and pure rutile TiO2. The platinum loaded and photo deposited rutile Titania is further analyzed for hydrogen production reaction by methanol reforming process. The rate of hydrogen evolution on platinum nanoparticle photo deposited on reforming process shows more than 900 μmol/g compared to pristine rutile titania catalysts.

Herein, we have reported a simple sonochemical synthesis of multi-layer graphene covered tungsten trioxide nanoballs (WO3 NBs) and the nanocomposite was characterized by FESEM, HRTEM, XRD, XPS, CV and EIS. Furthermore, progesterone (PGT) is a preferred marker for various biological problems like pregnancy problem, mood swings, anxiety, depression, nervousness and body pain. Therefore, its selective and sensitive determination in various biological fluids is beneficial for the evaluation of malformation problems. We describe the fabrication of an amperometric and non-enzymatic biosensor based on WO3 NBs@GR nanocomposite modified electrode for nanomolar detection of PGT. The results showed that the nanocomposite modified electrode exhibit well-defined electro-oxidation peak compared to bare and control electrodes, demonstrating the superior electrocatalytic ability and performances. The fabricated modified sensor was facilitates the analysis of PGT in the concentration ranges of 0.025–1792.5 µM with a low detection limit of 4.28 nM. Further, the as-prepared WO3 NBs@GR electrode has been applied to determination of PGT in human blood samples with outstanding recovery results and more importantly, the facile and environment-friendly sonochemical construction strategy extended here, may be open a cost-effective way for setting up the nanocomposites based (bio) sensing platform.

In continuation to our earlier work on nickel (Ni)-arsenate (As) composite, the current work deals with the electrical conductivity and mechanical resistivity of the same composite by means of its further reinforcement with the polylactic acid (PLA) polymer. For the PLA-Ni-As composite, we understand from the electrochemical studies that the conductivity is strongly influenced by the temperature and due to the presence of external electrolyte. The DC electrical conductivity approach used for the temperature dependency provided the information that the conductivity falls in the semiconductor zone ranging at 10−3 S cm−1, thereby indicating that it followed the Arrhenius equation. In addition, we found in terms of the mechanical properties that the PLA-Ni-As composite outperformed the plain, untreated Ni-As composite by reducing the activation energy. For the mechanical resistivity studies we found that the 25% PLA-loaded Ni-As material significantly improved the tensile strength and modulus, elongation at break %, impact properties and also the flexural strength and modulus as against the plain and other combinations due to enhanced interfacial interactions. The cell viability and proliferations studies tested against two different cell lines provided the information that the presence of polymer reduces the toxic response of arsenic material. From the cumulative analysis therefore, we indicate that the PLA-Ni-As composite can be a potential candidate to find its uses in the electrochemical and solar cells, in addition to automotive and aerospace industry.

In this paper, perovskite-type SrTiO3 nanocubes decorated reduced graphene oxide is synthesized by sonochemical method. The as-synthesized SrTiO3@RGO nanocomposite was confirmed by XRD, TEM, SEM, elemental mapping and electrochemical technique. Furthermore, surface morphological and X-ray diffraction studies revealed the formation and high loading of SrTiO3 nanocubes on reduced graphene oxide matrix. The SrTiO3@RGO nanocomposite modified electrode shows an excellent electrochemical detection towards of amino acid (tryptophan). The developed sensor was showed a wide linear range from 30 nM to 917.3 µM and detection limit is 7.15 nM. Furthermore, the sensitivity was calculated to be 9.11 µA µM−1 cm2. In addition, the proposed modified sensor is exhibited good selectivity, stability, reproducibility and repeatability. The SrTiO3@RGO catalyst modified electrode was successfully applied to tryptophan analysis in biological samples.

In this study, we studied the DNA extraction capability of poly(4,4′-cyclohexylidene bisphenol oxalate) following the surface modification and composite formation with that of microcrystalline cellulose (MCC) and magnetic iron oxide nanoparticles (NPs). The physical characterization techniques like scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, energy-dispersive X-ray analysis (EDX), and thermogravimetric analysis (TGA) were employed for the poly(bisphenol Z oxalate)-MCC-magnetite composite during different stages of its formation. The results confirmed the successful modification of the polymer surface. On testing in the presence of three types of binding buffers, a high value of 72.4% (out of 10,000 ng/μL) efficiency with a total yield of DNA at 2×106 ng and absorbance ratio of A260/A280 (1.980) was observed for the 2 M GuHCl/EtOH binding buffer. These results were compared against the other two buffers of phosphate-buffered saline (PBS) and NaCl. The lowest value of DNA extraction efficiency at 8125 ng/μL of 58.845% with absorbance ratios of A260/A280 (1.818) for PBS was also observed. The study has concluded an enhancement in the DNA extraction efficiency when the polymer is in the composite stage along with cellulose and magnetite particles as compared against the bare polymer.

The different type of halide modified mesoporous silica catalysts were prepared via post-grafting technique using meso-silica derived from rich husk by simple sol-gel method. The physico chemical characterizations of as prepared catalysts were characterized using FT-IR, N2-sorption-desorption study, 13C CP/MAS NMR and SEM techniques. FT-IR and 13C CP/MAS NMR revealed the effective anchorage of imidazole and 1,2-dihaloethane on the MCM-41. SEM analysis images shows the comprise worm-like agglomerated structure which was similar to MCM-41. The catalysts were then used in cycloaddition of carbon dioxide and phenyl glycidyl ether under solvent free or less conditions. Among the prepared catalyst, Br-immobilized MCM-41 shows higher catalytic activity (96.7%) under ambient reaction by adopting following conditions such as 100 °C, 20 bar initial CO2 pressure, 300 mg catalyst mass and 3 h. The conversion of phenyl glycidyl ether using ImI-MCM-41 and ImCl-MCM-41 are 77.3% and 26.4% respectively. The catalytic results are confirmed that the synergistic effect owing to the stronger nucleophilicity of bromide− and amine could be promoted the reaction smoothly. The catalyst was recovered and reused for four times without a significant decrease in activity or product selectivity. A possible site for CO2 activation by ImBr-MCM-41 catalyst could be the potential ionic liquid mimic's halide immobilized MCM-41 like material for efficient conversion of the substrates such as phenyl glycidyl ether and Epoxy hexane for cycloaddition reactions have been demonstrated.

In view of the methyl orange (MO) dye on everyday applications in the textile, food, leather, paper, printing, and pharmaceuticals industry, in addition to its toxic behaviour on human health, we have developed a biodegradable polylactic acid (PLA)-based cerium dioxide (CeO2)-graphene oxide (GO) composite by means of a sol-gel technique and tested its efficacy. For the study, the PLA polymer obtained is of renewable agriculture waste origin (sugarcane bagasse) and was isolated by means of fermentation of the feedstock followed by the polymerization of lactic acid. The instrumental techniques such as the powdered x-ray diffraction, scanning electron microscopy etc. were employed for the physical characterization of the material. The various parameters such as the kinetics, desorption, regeneration, pH, isotherm theories, and ionic strength were tested towards the adsorption of MO dye onto the surface of GO-PLA-CeO2 composite. The outcome of the study exhibited that the GO-PLA-CeO2 composite revealed promising behaviour for the dye removal, which was allocated to the efficacy of GO, PLA, and CeO2 properties. Also, the adsorption process of GO-PLA-CeO2 is completely dependent on the initial concentration of MO and the adsorption equilibrium fitted well with the Langmuir isotherm. In addition, the electrochemical characterization of the composite was studied by means of CV and impedance measurements. Based on the outcome of the results, it can be said that the GO-PLA-CeO2 composite may be applied as a suitable electrode material along with its efficient adsorption properties for the removal of MO dye from wastewater.

Cobalt oxide nanorods were successfully synthesized by a hot plate combustion method using the plant extract of Vitis vinifera. The plant extract as an alternative to toxic chemicals can be used generally as reducing and capping agents. The obtained nanorods were characterized by XRD, FT-IR, Raman, TEM, SAED, EDX, DRS, PL and VSM techniques for the structural, morphological, optical and magnetic properties. The XRD, FT-IR, Raman, EDX analysis confirmed the high purity of the sample. The TEM and SAED results showed the rod shape morphology of the sample. DRS and PL showed the band gap energy and emission at visible region. VSM showed the antiferromagnetic nature of the sample. The photocatalytic activities of the as-prepared cobalt oxide nanorods were investigated for the degradation of textile dying waste water. As per the standards of Indian pollution control board for industrial waste water let out into river bodies, the degradation reactions of waste water was found to be 250 mg/L at 150 min. Also, the same catalyst is used for the reduction of 4-nitrophenol and 4-nitroaniline using sodium borohydride as a reducing agent and it exhibits excellent reduction reaction, because of the high active surface sites. The time taken for the reduction reaction was 300 sec and 210 sec for 4-nitrophenol and 4-nitroaniline respectively. Also, the antibacterial activities towards the bacterial strains were studied and reported.

Heterobimetallic complexes [Cu(L)Sn(CH3)2(H2O)(Cl)] (3) and [Zn(L)Sn(CH3)2(H2O)(Cl)] (4) have been synthesized from their monometallic analogs [Cu(L)(H2O)(Cl)] (1) and [Zn(L)(H2O)(Cl)] (2) of Schiff base ligand (L) which were characterized by various spectroscopic and analytical methods. DFT calculations were carried out to simulate the vibrational spectra to support the anticipated structures. The interaction studies of ligand (L) and complexes (1–4) with CT–DNA were performed by employing UV–vis, and fluorescence spectroscopic techniques which revealed that heterobimetallic complexes 3 and 4 showed higher affinity with DNA due to dual mode of action as compared to monometallic complexes 1 and 2. Further, validation of the interaction studies was accomplished by carrying out molecular docking studies with DNA. Gel assay displayed that both the complexes have ability to cleave DNA efficiently and are specific minor groove binders. CuII–SnIV complex 3 cleaved pBR322 DNA via oxidative mechanism, while ZnII–SnIV complex 4 followed hydrolytic cleavage pathway. In vitro cytotoxicity evaluation of complex 3 was tested on a different cancer cell lines showing promising antitumor activity. Communicated by Ramaswamy H. Sarma

Anti-amyloidogenic activity of safranal towards induced HSA amyloids has been observed using a variety of techniques including fluorescence, UV–visible, CD, DLS and microscopies. The HSA solution was pre-incubated at 65 °C for 120 h and, in between, the growth of amyloid fibrils, using ThT aggregation kinetics, was monitored at different time intervals. It was found that the amyloid fibril formation of HSA diminishes in presence of safranal and the inhibition was concentration dependent. The surface hydrophobicity of HSA amyloid fibrils also decreased in presence of safranal. The increased CR binding of HSA fibrils also decreased and high concentration of safranal causes the CR binding to resemble like that of native HSA. Both RLS and turbidity intensities were also in inverse relation to the safranal concentration. Safranal also has a good impact to protect the secondary structure of incubated HSA. From the electron microscopy it was seen that the fibrillar network of HSA amyloids gradually vanishes as the concentration of safranal increased. The largely decreased population of HSA aggregates in safranal containing solution as compared to the one without it also suggests the inhibition of formation of large fibrillar aggregates.

The silane amide precursors were prepared by amidation of oleic and stearic acid with γ-aminopropyltriethoxysilane. The stearyl and oleyl amines were added to vinyl trimethoxy silane to synthesize aminosilane precursors. The chemical structures, surface morphology, thermal stability of the prepared hydrophobic silica nanoparticles were investigated. The wetting characteristics, mechanical properties, thermal stability and corrosion resistance of the prepared hydrophobic silica nanoparticles with epoxy composites coated on the steel panels were studied. The data confirm that the all the prepared hydrophobic silica show higher contact angles (100-110°) when blended with epoxy up to 3Wt %. Moreover, the dispersion, hydrophobicity and paraffin wax contents of silica nanoparticles embedded into epoxy networks control the high corrosion resistivity of the composites as organic coatings of steel substrate. The salt spray resistance data elucidate that the epoxy modified with 1 Wt % of the hydrophobic silica/paraffin wax achieved higher salt spray resistances up to 1500 h with high rating.

Molecular interaction between BSA and safranal was seen in the present study using experimental and molecular docking methods, in addition, inhibitory effect of safranal towards BSA amyloid formation was also seen. UV–visible and fluorescence studies suggested the formation of 1:1 complex between BSA and safranal via static quenching mechanism. The corrected fluorescence spectra showed a blue shift in the emission maximum on the successive addition of safranal which revealed the involvement of hydrophobic forces in the interaction. Far-UV CD measurements suggested the stabilization of secondary structure of BSA by increasing its α-helical contents, i.e., compaction of protein and that was further supported by RLS and DLS methods. Analysis of thermodynamic parameters presented that hydrophobic forces as well as hydrogen bonding were involved in the binding. From the competitive assay and molecular docking simulations it was found that safranal binds near the Sudlow's site 1 in the subdomain IIA and most of the amino acids residues bound with hydrophobic forces and a few with hydrogen bonding. Safranal was found to inhibit the BSA amyloid formation and the inhibition was concentration dependent. Exposed surface hydrophobicity of BSA amyloid fibrils was decreased considerably in presence of safranal.

Fluorescent labeling is limited to certain molecules and alters biomolecule functionality. A new class of nanomaterial with anticancer activity and fluorescence properties has been designed and prepared. This nanotherapeutic conjugate of natural molecules has a selective binding site in cancer cell lines. Natural drug umbelliferone was taken with cobalt metal ions in a one pot assembly in the presence of tannic acid which yields new fluorescent nanoparticles of umbelliferone cobalt oxide nanoconjugate. Umbelliferone has high fluorescent properties and also has coordination ability to bind with central metal ions. The nanoconjugate was synthesized and characterized by using TEM, EDX analysis, SEM, XRD, and FTIR spectroscopy. TEM shows that the average size of the particles formed with umbelliferone is ∼20 nm. The solubility of the drug nanoparticles in water showed compatibility with cancer cells and provided a favorable environment to investigate the mechanism of action on the MCF-7 cell line. The nanoconjugate is microcrystalline in nature and gives a clear suspension in water. The nanocobalt conjugate was loaded on TiO2 nanoparticles by ultrasonication, and the solution was digested overnight. The conjugate of the drug with a TiO2 drug carrier was stable in solution and maintained the nanostructure ∼34.6 nm. A comparative study with nano-vehicle TiO2 and the nanoconjugate was performed. TiO2 was used to compare the anti-cancer activity of the nanoconjugate at low dose in vitro. It was observed that the nanoconjugate with TiO2 is capable of reaching the specific target like the TiO2 nanoparticle and enhance the chemotherapeutic impact. Hence, the nanoconjugate can also be used like nano-TiO2, as the drug and carrier. The ct-DNA and HSA protein binding studies were done and validated by docking studies.

The oil spill represents one of the most important pollution sources for marine environments, that occurs due to tanker collisions, ship accidents, and platforms. Several techniques are used for treating oil spill disasters including chemical, physical, and biochemical. The use of chemicals, magnetite nanomaterials (MNMs) in particular, is one of the most applied techniques used for oil spill remediation due to their low cost, fast remediation, and reusability. This work aims to synthesize and use new ionic liquids (ILs) for the modification of MNMs surfaces to enhance their performance for crude oil uptake. For that, octadecylamine (OA) was reacted with epichlorohydrin (EH), followed by reaction with either diethylenetriamine (DT), or tetraethylenepentamine (TP) to obtain corresponding amines, OADT, and OATP, respectively. The produced amines were quaternized using acetic acid (AA) forming corresponding ILs, OADT-IL, and OATP-IL. The obtained ILs, OADT-IL, and OATP-IL were applied for modification of magnetite nanomaterials (MNMs) surface to obtain the surface-modified MNMs, DT-MNMs, and TP-MNMs, respectively. The surface-modified MNMs were characterized using different techniques including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and contact angle. The efficacy of DT-MNMs, and TP-MNMs for heavy crude oil uptake (EMU) was evaluated. Further, the factors affecting on the crude oil uptake including MNMs: heavy crude oil ratio, and contact time were also evaluated. The data exhibited that, the EMU relatively declined as the ratio of DT-MNMs, and TP-MNMs decreased. Even at low MNMs:crude oil ratio (1:50), DT-MNMs, and TP-MNMs displayed EMU 87%, and 90%, respectively, which means 1 g of either DT-MNMs, or TP-MNMs can uptake 45 g, or 43.5 g, respectively. These values are high as compared with other studies that reported the use of MNMs for oil spill cleanup. Furthermore, the data indicated that the EMU increased as the contact time increased, and reached maximum EMU of 98% for both MNMs samples after 10 min.

Development of new hybrid laminated composites of Kevlar-29 (K-29)/banana fiber ( Musa acuminata) mats to meet future demand for fiber reinforced polymer (FRP) composites has been investigated. The different ply-stacking sequenced Kevlar (K)/natural (N) banana reinforced epoxy polymeric hybrid composite samples were designated as KN1, KN2, KN3, KN4, KN5 and KN6, in addition to NN7 and KK8 for single or non-hybrid FRP (control) composite samples. The ply-stacking effects on mechanical properties of all the laminated composite were investigated. The maximum tensile, flexural, impact and interlaminar shear strengths (ILSS) were obtained with sample KN4, because of the stacking of its Kevlar and natural banana mats, which was K2/N4/K2 of 8 layers and different from other stacking sequences. The percentage improvements on tensile strength of sample KN4 when compared with other hybrid composite samples KN1, KN2, KN3, KN5 and KN6 were 6.3, 4.4, 3.6, 13.1 and 11.3%, respectively. While, same optimum sample KN4 recorded highest flexural strength among hybrid samples with percentage improvements of 122.19, 70.97, 31.03 and 83.68% when compared with other hybrid samples KN2, KN3, KN5 and KN6, respectively. Similar trend of results was obtained for their tensile and flexural moduli. But, both hybrid composite samples KN3 and KN4 recorded higher impact strengths of 3.0 and 2.8 J, respectively, when compared with other hybrid counterparts. The tensile and flexural strengths of sample KN4 were 147.48 and 223.69 MPa, respectively. The tensile properties of various theoretical model were compared with experimental values.

Herein we have studied the noncovalent molecular interactions between hen egg white lysozyme (HEWL) and the commonly employed antineoplastic drug gemcitabine through the cumulative implementation of spectroscopic techniques and in silico approaches. The formation of a complex between HEWL and gemcitabine was made evident by the differences between the UV-visible spectra of the protein and protein-gemcitabine complex. Fluorescence quenching of HEWL by gemcitabine was hardly detectable at room temperature, but it became prominent at higher temperatures. Very low values for the bimolecular quenching constant and the non-reciprocal dependence of quenching on temperature indicated that dynamic quenching was taking place. Analysis of experimental data indicated that the interaction was dominated by hydrophobic forces, while the results of a computational investigation suggested the concomitant contribution of hydrogen bonding. Gemcitabine binding induced modifications of the secondary structure of HEWL by slightly increasing the α-helical content of the protein. Finally, gemcitabine binding site was inferred to be located in HEWL big hydrophobic cavity.

Preparation of new green oilfield chemicals based on ionic liquids (ILs) having higher demulsification efficiency to solve the heavy crude oil brine water emulsions became a target in the petroleum research studies and industry. In the present work, the combination of pyridinium, imidazolium, and hydrophilic or hydrophobic moieties in the chemical structure of ILs has been investigated to improve the surface properties of ILs in both bulk solution and interfaces. Aminopyridine was quaternized with cetylbromide and condensed with glyoxal and 4-hydroxybenzaldehyde in acetic acid to prepare imidazolium-pyridinium bromide acetate ionic liquid (IPy-IL). The phenol group of IPy-IL was etherified with tetraethylene glycol to alter its amphiphilicity and synthesize new amphiphiles (AIPy-IL). Their chemical structure, thermal characteristics, and stabilities were characterized. Their aqueous solution performance in seawater was evaluated to investigate their surface activity, aggregation particle sizes, and surface charges. The demulsification performances of the prepared Arabic heavy crude oil seawater emulsions in the presence of different concentrations of IPy-IL and AIPy-IL were evaluated and proved by interfacial tension, particle size, and demulsification efficiencies at a temperature of 45 °C. The data concluded that AIPy-IL was an effective demulsifier for different crude oil seawater emulsion compositions at a low injection dose and temperature of 100 ppm and 45 °C, which were not report elsewhere.

In an attempt to identify suitable nano-carriers for drug delivery, natural drug umbelliferone was chosen to synthesize new modulated nanoconjugate of umbelliferone cobalt oxide with cobalt (II) nitrate in one pot assembly in the presence of tannic acid. The synthesized nanoconjugate drug (NCD) was then loaded on graphene oxide (GO) as drug carrier by simple ultrasonication method and thoroughly characterized by various spectroscopic techniques (FT-IR, SEM, TEM, XRD, EPR and thermogravimetric analysis) which revealed the successful loading of the nanoconjugate drug on GO. The UV-visible, fluorescence and electrochemical studies suggested that strong π-π stacking interactions exist between nanoconjugate drug and GO. The binding studies of NCD-GO with ct-DNA were performed by various optical and biophysical methods

Imidazolium ionic liquid (IIL) was prepared from aminolysis of polyethylene terephthalate (PET) waste with pentaethylenehexamine (PEHA) to apply as hardener of epoxy resin. Its purified chemical structures, thermal stability, and thermal characteristics were identified as well as amino phthalamide aminolyzed products. The thermal, thermomechanical, and mechanical properties of the cured epoxy resins with different weight percentages of IIL were investigated to optimize the best weight ratio to obtain homogeneous networks. The adhesion, durability, and corrosion resistance of the cured epoxy resins on the steel surfaces were tested to confirm that the best weight ratio of epoxy: IL was 2:1. This ratio achieved higher adhesion strength and salt spray resistance to seawater extended to 1500 h.

New magnetic imidazolium ionic liquid (IIL) was synthesized to improve the curing, mechanical, and thermal characteristics of the epoxy/polyamine system. In this respect, 2-(4-minophenyl)-1.3-bis(triethoxysilyl)-1H-imidazol-3-ium acetate as IIL was synthesized and characterized by different spectroscopy tools. The IIL was used as capping to prepare Fe3O4 nanoparticles (NPs) as new Fe3O4-IIL NPs. The thermal stability, morphology, crystal lattice structures, and magnetic properties were evaluated to confirm the formation of uniform, thermal, stable, and superparamagnetic Fe3O4-IIL NPs. The prepared Fe3O4-IIL NPs were mixed with an epoxy/polyamine system to improve the curing, thermal, and mechanical properties of epoxy through chemical reactions. The dynamic mechanical analyzer and differential scanning calorimeter were used to investigate the flexibility and storage modulus of the cured epoxy/polyamine system in the absence and presence of Fe3O4-IIL NPs. The atomic force microscope and scanning electron microscope were used to evaluate the dispersion and embedding of Fe3O4-IIL NPs into epoxy matrix. The thermal, mechanical, and surface morphologies data confirmed that the incorporation of Fe3O4-IIL NPs using 3 wt. % during the curing of an epoxy/polyamine system produces superior epoxy films without cracks, holes, and NPs agglomeration.

Although the material hydroxyapatite (HAP) has excellent porous, biocompatible, and biodegradable properties, its mechanical strength and microbial inhibition rate are not adequate for its direct use in bone tissue engineering or in constructing artificial teeth. To overcome some of its limitations, in the present study, we have formed an organic-inorganic composite with an altered internal structureviadoping selenium (Se) cations into the lattice of HAP. We have synthesized Se-substituted HAP (Se-HAP) composites with different Se/P ratios (0.01, 0.05, and 0.1 M)viaa wet chemical route in which two different sets of samples were collected (1) after only precipitation (referred to as the precipitation method) and (2) after precipitation followed by sonication (referred to as the sonochemical method). FTIR and Raman spectroscopic analyses confirmed the successful doping of Se into the HAP matrices, while powder XRD studies indicated their highly crystalline nature, which was significantly influenced by Se doping. The XRD data also showed that the Se-HAP particles formed by the precipitation method have a size of 56 nm and those formed by the sonochemical method have a size of 29 nm. Morphological analysis by means of SEM and TEM indicated that the sonochemical method produces well-defined rod-shaped particles, while the precipitation method produces particles with agglomerated structures. Hemolytic studies confirmed that the Se-HAP particles are biocompatible, and that the hemolytic ratio increases with the Se content. In addition, antibacterial studies indicated that Se-HAP responds quite well against a Gram-positive strain (S. aureus), on a par with the response to a Gram-negative strain (P. aeruginosa). Finally,in vitrocell viability and proliferation studies indicated an increase in the proliferation capacity of non-cancer cells (NIH-3T3 fibroblasts) and a considerable reduction in the viability of cancer cells (MG-63 osteosarcoma). Based on the overall analysis, the Se-HAP samples formed by the sonochemical approach could have potential for biomedical applications in bone cell repair, growth, and regeneration.

In this study, an electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles (SiNWs/PtNPs) on a screen-printed carbon electrode (SPCE) for the detection of

The designing of multifunctional materials in system-level efficiency is one of the main targets and a hot topic for the application of novel green or bio-based materials and structures. In this work, the chemical structure of bio-based cardanol that was derived from cashew oil was modified through a reaction with a bishydrazino-s-triazine derivative followed by condensation polymerization or reaction with terephthaldehyde to obtain a Schiff base polymer. The chemical structures of the modified cardanol-bishydrazino-s-triazine-based monomer and the Schiff base polymer were confirmed from FTIR and NMR spectroscopy analyses. The modified cardanol bishydrazino-s-triazine monomer and polymer were added with different weight ratios during the curing of the epoxy/polyamine hardener to improve the thermal, mechanical, and anti-corrosion characteristics of the epoxy coating of a steel substrate. The data elucidated that the presence of a cardanol bishydrazino-s-triazine monomer and polymer improves the thermal, mechanical, adhesion, and anti-corrosion characteristics of epoxy coatings after exposure for more than 1500 h. The presence of a cardanol- bishydrazino-s-triazine polymer more than 3 wt.% during the curing of epoxy networks produces superhydrophobic and self-healing epoxy coatings. The modification of the epoxy coating with the cardanol bishydrazino-s-triazine polymer improves the seawater contact angle by more than 150&deg, and the adhesion strength of the epoxy coating with the steel surface.

A new series of lanthanum(iii) complexes was synthesized using a

The demulsification of water-in-heavy crude oil emulsion with water droplet size in the microscale has drawn great attention because of their high stability and difficulty of separation. In the present work, a series of ethylene amine-based demulsifiers were prepared in one step through the interaction of pentaethylene hexamine, tetraethylene pentamine, and triethylene tetramene with glycidyl 4-nonylphenyl ether. The amphiphilic polyethyleneimine (APEI) abbreviated as DNPA-6, DNPA-5, and DNPA-4 were prepared to adjust their hydrophile–lipophile balances (HLB) to meet the requirement of the demulsification. 1HNMR, 13CNMR, and FTIR spectra were utilized to verify their chemical structures. The surface properties and zeta potential were also investigated. Demulsifier dose, separation time, and HLB values were taken into account to evaluate the demulsification efficiency of the synthesized APEI. The results suggested that the prepared demulsifiers had high ability to reduce the surface and interfacial tensions and also broke successfully water-in-Arabian heavy crude oil emulsions. The demulsification efficiency of DNPA-5 reached 100% for crude oil/water emulsion (90/10 vol %).

The designing of metal-based anticancer therapeutic agents can be optimized in a better and rapid way if the ligands utilized have standalone properties. Therefore, even when the organometallic/coordination complex (i.e., metallodrug) gets dissociated in extreme conditions, the ligand can endorse its biological properties. Herein, we have synthesized and characterized ɳ6-p-cymene ruthenium diclofenac complex. Furthermore, the ruthenium complex interactions with human serum albumin (HSA) and ct-DNA have been studied using various spectroscopic studies viz., UV, fluorescence, and circular dichroism and exhibited a significant binding propensity. Furthermore, in vitro cytotoxicity assays were carried out against human breast cancer “MCF-7” cell line. The ɳ6-p-cymene ruthenium diclofenac complex registered significant cytotoxicity with an IC50 value of ∼25.0 µM which is comparable to the standard drugs. The ɳ6-p-cymene ruthenium diclofenac complex was able to decrease the MCF-7 cell proliferation and induced significant levels of apoptosis with relatively low toxicity.

Ionic liquids (ILs) are environmentally friendly compounds and their gemini types exhibit high thermal stabilities and high surface and interfacial activity. The main objective of this work is to prepare, characterize and investigate the demulsification efficiency of two gemini pyridinium surfactant ILs. They were prepared by the introduction of long chain decanoyl chloride to aminopyridine followed by quaternization with two dichloro spacers containing different ethylene oxide units (DCDE and TEGDC) to form MEGPy and TEGPy ILs, respectively. The structure properties of the prepared demulsifiers were investigated using different spectral tools including 1HNMR and 13CNMR and DLS. Also, their solubility and surface activity were investigated to confirm their ability to reduce surface tension (ST) and interfacial tension (IFT). Gemini pyridinium IL with triethylene oxide spacer (TEGP) showed higher ability to reduce both ST and IFT than that with mono ethylene oxide spacer (MEGP). Thanks to the ability of both TEGPy and MEGPy surfactant IL to reduce ST and IFT, they were applied successfully as demulsifiers for W/O emulsions with different water percentages. Demulsification study indicated that both TEGPy and MEGPy were able to demusify W/O emulsions with high performance which reached to 100% at low concentrations (250 ppm) for some compositions with higher activity to TEGP IL than MEGPy surfactant.

In this study, Eight new transition metal complexes (Co(II), Ni(II), Cu(II), and Zn(II)) were obtained via condensation with thiophene-appended nicotinic acid hydrazide ligands (L5 and L6), synthesized and characterized structurally by spectroscopically and thermogravimetrically. We study the catalytic properties by multi-component Biginelli reaction with catalytic amount of our transition metal complexesin the presence of solvent. While increasing the catalyst concentration from 1.414 × 10−2mmol into 8.486 × 10−2 mmol there is no appreciable change. In vitro anti-cancer activity of L5 & L6 and their metal complexes was done on human colorectal cancer HT29 cell line, the synthesized metal complexes showed higher anti-proliferative activity at lower concentrations compared to the free ligands alone. The synthesized molecules can be extended into 2D and 3D supramolecular networking through π-π stacking, H-bonding and hydrophobic contactsbythe receptor thymidylate synthase. Antibacterial activity of synthesized Co(II) and Zn(II) complexes showed significant inhibition on the growth of both gram positive and gram negative bacteria compare to the free L5 and L6 ligands.These results were display that thiophene-appended nicotinic acid hydrazidederivatives, in particularlycomplexes L5–Zn(II) and L5-Co(II), might be used for the design of new antineoplastic agents.

Retraction of ‘Anti-cancer activity of hierarchical ZSM-5 zeolites synthesized from rice-based waste materials’ by S. K. Jesudoss et al., RSC Adv., 2018, 8, 481–490, https://doi.org/10.1039/C7RA11763A.

A novel hybrid nanomaterial based on silver nanoparticles, AgNPs, supported by 2,4-dihydrazino-6-(methoxypolyethyleneglycol)-1,3,5-triazine (mPEGTH) was prepared using solid phase technique. The synthesis process and the structural properties of the AgNPs were analyzed through X-ray diffraction (XRD), thermogravimetric analysis (TGA), transmittance and scanning electron microscopy (TEM and SEM). The effect of seawater, and pH of solutions on the aggregation and zeta potential of Ag NPs were characterized and identified. The Ag/mPEGTH, hybrid materials produced well dispersion and exhibit a remarkable superiority in enhancing the anticorrosion performance of epoxy coatings and fulfill a significant synergistic effect in anticorrosion and self-healing performance for epoxy composite coatings. The new self-healing mechanism of Ag/mPEGTH nanomaterial for the epoxy coating defects is tentatively proposed and discussed.

For determining the pharmacological properties of medicinal compounds, their binding with serum albumins is very crucial. Herein, we have selected safranal, a major constituent of saffron which is known to retain a number of medicinal properties including antioxidant, anti-inflammatory, tumoricidal, anti-genotoxic, and anti-aging activities; and studied its mechanism of binding with human serum albumin at physiological pH using various spectroscopic methods along with computational approach using molecular docking. A change in the difference UV-visible spectrum of HSA in presence of safranal was found which is due to the complex formation. Owing to the strong absorption of safranal at the fluorescence excitation wavelength of HSA (295 nm) and in the whole range of emission, the fluorescence spectra of HSA in presence of safranal were corrected for the inner filter effect. After the correction the spectra were free from the safranal absorption effect and it was found that addition of safranal causes the quenching of HSA fluorescence and a blue shift of the emission maximum which are attributed to the binding of safranal to the protein and dominance of hydrophobic forces in the interaction, respectively. It was evident from the comparison of observed and corrected fluorescence spectra that before correction there was a large red shift while after correction appearance of blue shift was occurred. The involvement of hydrophobic interaction was also found from the extrinsic fluorescence measurements using ANS dye as well as from the analyzed thermodynamic parameters. Safranal was found to partially induce the secondary structure of HSA as construed from the CD measurements. The size of the HSA was also decreased as evident from the DLS and RLS measurements. Both site marker studies and molecular docking simulations suggested that the primary binding site of the safranal in the HSA is Sudlow's site 1 located in the subdomain IIA. Hydrophobic interaction provides the major contribution to the binding forces along with a little amount of hydrogen bonding.

New crosslinked Poly(ionic liquids), PILs, cryogels based on 2-acrylamido- 2-methylpropane sulfonic acid, AMPS, were prepared and copolymerized with acrylic acid, acrylamide or 2-hydroxyethyl methacrylate in the presence of triethanolamine. The crosslinking copolymerization of AMPS were carried in the presence of water at cooling temperature in the presence of amoniumpersulfate, N,N, N′, N′ tetramethylethylenediamine and N , N ′-methylenebisacrylamide as radical initiator, activator and crosslinker, respectively. The chemical structures, surface morphologies of the PILs cryogels were investigated. The PILs cryogels showed high thermal stability and interconnected pores. The cryogels achieved high adsorption capacity as 1228 mg·g −1 for removal of MB from aqueous solution during contact times ranged from 5 to 10 min. New mechanism for chemisorption of MB with the active centers of PIL cryogels is proposed and elucidated.

An n-butyl bromide/sodium dodecyl sulfate/n-butanol/water microemulsion system was chosen as a model of an organohalide-containing microemulsion. Two systems were prepared using the Bourayne method...

The present study deal with the fabrication of low cost nanocomposite based electrodes based on Nickel foam binder free substrate for supercapacitor applications. The composition of nanocomposite is molybdenum sulphide nanoparticle/graphene coated on mesoporous manganese oxide. The first step is to involve the preparation of mesoporous manganese oxide by non-ionic surfactant assisted method. In the second stage is to deposit the reduced graphene on mesoporous manganese oxide in the presence of ultrasonic irradiation followed by addition of known quantity of commercial MoS2 nanopowder (particle size below 90 nm). The manganese oxide based nanocomposite is showing porous architecture with graphene sheet formation together with MoS2 nanoparticle deposition. N2 adsorption-desorption Isotherm curves for MoS2 nanoparticle (NP) modified graphene oxide/meso-MnO2 and pure meso-MnO2 displayed type IV isotherm with improved surface area values. The reduced graphene oxide (graphene) and MoS2 exist in the form of glassy flaky morphology as well as tubular/needle shapes are obtained after the deposition process in the final nanocomposite. The orderly arranged and anchored nano-sized mesoporous manganese oxide nanocomposites are showed increased specific capacitance (up to 527, 727 and 1160 F/g) and continuous cyclic stability.

New pH-sensitive polystyrene, PS, and poly(4-vinylpyridine), P4-VP, nanospheres were prepared by using surfactant-free method based on soft microgels (Mickering emulsion). The formation of stable Mickering cyclohexane/water emulsions was investigated by using soft microgel particles of poly(acrylamide), PAAm, poly(2-acrylamido-2-methylpropane sulfonic acid), PAMPS, and sodium salt of PAMPS, PAMPS-Na, as stabilizers. The dynamic light scattering (DLS), optical microscopy, and scanning electron microscopy (SEM) were used to investigate the optimum conditions and effects of surrounding solutions on the microgels characteristics and their corresponding Mickering emulsions. The cyclohexane/water Mickering emulsions stabilized by softer and neutral charged microgels were considerably more stable under the same conditions. Furthermore, the stimuli-responsive properties of PAMPS microgel stabilized cyclohexane/water Mickering emulsions suggest the potential utility in the preparation of PS and P4-VP nanospheres. The effects of pH changes on the morphology, particle sizes, and surface charges of PS and P4-VP microgels were evaluated to prove the pH-sensitivity of the prepared nanospheres.

In this work, new smart mesoporous amine-functionalized silica nanoparticles were prepared from hydrolyzing microgels based on N-isopropyl acrylamide-co-vinyltrimethoxysilane microgels with tetraethoxysilicate and 3-aminopropyltriethoxysilane by sol-gel method. The thermal stability and Fourier transform infrared were used to determine the amine contents of the silica nanoparticles. The pH sensitivity of the synthesized silica nanoparticles in their aqueous solutions was evaluated by using dynamic light scattering (DLS) and zeta potential measurements. The porosity of the amine-functionalized silica nanoparticles was evaluated from a transmittance electron microscope and Brunauer-Emmett-Teller (BET) plot. The results have positively recommended the pH-sensitive amine-functionalized silica nanoparticles as one of the effective nano-adsorbent to remove 313 mg&middot, g&minus, 1 of CB-R250 water pollutant.

New hybrid nanomaterials based on Fe 3 O 4 and Ag/Ag 2 O nanoparticles (NPs) supported by 2,4-dihydrazino-6-(methoxypolyethyleneglycol)-1,3,5-triazine (mPEGTH) were successfully synthesized without using reducing agents in both solution and solid phases. The mechanism for Fe 3 O 4 and Ag/Ag 2 O NPs formation in the presence of mPEGTH, their chemical structures, surface morphologies, crystal structures, thermal stabilities and mPEGTH contents were characterized and identified. The effects of seawater salinity and pH of solutions on the Fe 3 O 4 and Ag/Ag 2 O NPs surface charges and particle sizes distributions were examined to investigate their performances under aggressive conditions. It was found that, the Fe 3 O 4 /mPEGTH, hybrid nanomaterials obtained good dispersed NPs and exhibit a remarkable superiority in enhancing the anticorrosion performance of epoxy coatings more than Ag/Ag 2 O NPs. The Fe 3 O 4 /mPEGTH nanomaterials achieved significant synergistic effect to improve the anticorrosion and self-healing performances for epoxy composite coatings. They achieved higher salt spray resistance up to 1500 h without rust formation. The new self-healing mechanism of Fe 3 O 4 /mPEGTH nanomaterials was tentatively discussed.

Herein, we report the synthesis and structural investigation of CuII-NaI heterobimetallic complex 1, which comprises of the compartmental Schiff-base ligand (H2L) derived from DACH (1,2-Diaminocyclohexane) and o-vanillin. B3LYP/TZVP DFT calculation was performed to get a deeper insight of the ground state electronic structure, and quantitative analysis of non-covalent interactions was carried out using Hirshfeld surface analysis to explore H-bonding, C-H···π, Cu···C-H and Cu···H-C interactions. Furthermore, in vitro DNA binding studies with Complex 1 demonstrated the electrostatic mode of interaction at the major groove of the DNA. Complex 1 showed the oxidative damage of pBR322 DNA via ROS generation. Additionally, in vitro cytotoxicity and genotoxicity of complex 1 were investigated on human breast cancer cells (MCF-7), revealed concentration-dependent cell viability at micromolar concentration level. Flow cytometric analysis confirmed the cytotoxic potential of complex 1 as the percentage of apoptotic cells were increased in the treatment group. Genotoxicity was evident in the induction of micronucleus and DNA fragmentation.

An organic–inorganic hybrid Zn(II) complex has been synthesized in a “zwitterionic” form which crystallizes in triclinic P1 space group possessing labile apical chlorine atoms. DNA interaction studies were performed to enunciate the binding strength. The hydrolytic cleavage potential of the complex was substantiated and the kinetic aspects of the mechanism followed are also discussed.

Abstarct Nanosized TiO2 and various transition metal ions (Fe, Co and Ni) doped TiO2 were prepared through hydrothermal method. Thermal analysis confirms the formation of crystalline TiO2. The powder X-ray diffraction patterns of all the materials show crystalline anatase TiO2 with crystallite size in the range of 22–23 nm. Raman spectra show respective modes corresponding to anatase TiO2 and also it coincides with the XRD data. The DR UV–vis spectra of 0.01 (Fe-, Co-, Ni)-TiO2 extends to the visible region (450–650 nm). The extended absorbance of these materials into the visible region provides enhanced photosensitive applications under sunlight. The degradation rate of Methylene blue (MB) was used to evaluate the photosensitive activity under visible light irradiation. Results suggest that 0.01Fe- TiO2, 0.01Co- TiO2 and 0.01Ni-TiO2 materials can potential be used for the generation of future fuel hydrogen by water splitting using solar radiation.

In the present study, iminodiacetic acid (IDA)-modified kenaf fiber, K-IDA formed by the chemical modification of plant kenaf biomass was tested for its efficacy as a sorbent material towards the purification of waste water. The K-IDA fiber was first characterized by the instrumental techniques like Fourier transform infrared (FTIR) analysis, elemental analysis (CHNSO), and scanning electron microscopy (SEM). On testing for the biosorption, we found that the K-IDA has an increment in the adsorption of Cu2+ ions as compared against the untreated fiber. The Cu2+ ions adsorption onto K-IDA fits very well with the Langmuir model and the adsorption maximum achieved to be 91.74mg/g. Further, the adsorption kinetics observed to be pseudo second-order kinetics model and the Cu2+ ions adsorption is a spontaneous endothermic process. The desorption study indicates a highest percentage of Cu2+ of 97.59% from K-IDA under 1M HCl solution against H2SO4 (72.59%) and HNO3 (68.66%). The reusability study indicates that the efficiency did not change much until the 4th cycle and also providing enough evidence for the engagement of our biodegradable K-IDA fiber towards the removal of Cu2+ ions in real-time waste water samples obtained from the electroplating and wood treatment industries.

The interaction between procainamide with ct-DNA was seen through several experimental and theoretical methods. The fluorescence intensity of procainamide decreased on increasing the concentration of ct-DNA and the quenching process was found to be static with approximately 1:1 binding between ct-DNA and procainamide. UV absorption spectroscopy gave an idea about minor groove binding which was further confirmed by the dye displacement method of DAPI/EtBr bounded ct-DNA interaction. Minor groove binding was also evidenced from the collective information obtained from DNA melting, viscosity and CD spectroscopy. Molecular docking simulations presented that procainamide bound in the minor groove (AT rich) region of B-DNA structures. From thermodynamic point of view the binding interaction between procainamide and ct-DNA was spontaneous process with liberation of energy and overall ordering of system. Hydrogen bonding was found to play important role as suggested by the values of thermodynamic parameters. Whereas from molecular docking simulations it was exposed that hydrogen bonding and hydrophobic interactions were crucial in the binding of ct-DNA and procainamide. DFT method was also used to calculate the Frontier molecular orbitals (HOMO and LUMO) of procainamide which were further used to calculate chemical potential (μ), chemical hardness (η) and fraction number of electrons (ΔN) from procainamide to DNA. Procainamide was found to act as electron donor to DNA bases excpet guanine. Finally, elucidation of anticancer activity revealed that procainamide possesses potential cytotoxicity against MCF-7 breast cancer cells and able to induce significant level of apoptosis at concentrations below IC50 value.

Labdane diterpenes are important substances due to their remarkable biological activities such as, antibacterial, antiprotozoal, antifungal and cytostatic and cytotoxic effects against human cancer cells. We have isolated a labdane diterpene named “leoheterin” from the aerial parts of the Otostegia fruticosa Forssk (Briq) obtained from south west Arabian mountains of Saudi Arabia. The isolated compound was characterized by 1HNMR, 13CNMR, IR and UV–visible spectroscopies. Due to the pharmaceutical importance of this class of compounds we have studied the interaction of HSA with leoheterin by using several spectroscopic methods. The change in the UV spectrum of HSA in presence of leoheterin gives a primary idea about the interaction between them. Congruently, leoheterin quenches the fluorescence of HSA with a prominent blue shift of 5 nm, reminiscent of involvement of hydrophobic interactions. There was 1:1 binding between leoheterin and albumin which was taken place via static quenching mechanism. From CD it was revealed that leoheterin induces the secondary structure of HSA which is further supported by 3-d fluorescence measurements which shows a decrease in the size of the HSA-leoheterin complex as compared to the HSA alone. Molecular docking simulations presented that among the first three conformers, which have been arranged according to the least binding energies and are also in good corroboration with the free energies of binding obtained experimentally, the first two conformers shown the binding in hemin binding site of subdomain IB while in third conformer the binding site was near to the drug binding site 1 located in subdomain IIA. All conformers exhibited the involvement of hydrogen bonding as well as hydrophobic interactions.