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This work addresses manufacture, testing and simulation of foot valve lever (FVL) for monoblock pump industry, using a cost-effective casting design process. The impact of different types of sands, such as air-set, dry and sodium silicate as well as gating designs, namely H-, U- and O-type, were studied with respect to surface roughness and porosity. The mold pattern was produced using additive manufacturing (AM) technology. Both experimental and numerical investigations were performed on the temperature distribution of molten metal at random locations for the different gating configurations or designs, considering mold filling and solidification. It was evident from the experimental investigation that contribution of air-set sand and O-type gating architecture showed limited consistency effects. Importantly, gating architecture was the most influential parameter to determine all specified quality outcomes, independent of sand mold. An order of O

The present work proposes an improved multi-gate designs (MGDs) in sand casting process, using both experimental and simulation (FLOW 3D) approaches, aiming to produce defect-free component. In this regard, the variant MGDs were developed and compared with the existing designs reported in the previous studies. Accordingly, the following new MGDs: side sprue serial connection (SSSC), centre sprue serial connection (CSSC), side sprue parallel connection (SSPC), centre sprue parallel connection (CSPC) and centre sprue runner extension parallel connection (CS-RE-PC) were modelled for both techniques. The experimental set-ups were developed for the aforementioned designs to study the flow behaviour of aluminium alloy and water. The validity of aluminium alloy flow characteristics in closed mould condition was checked with the water mould experimentation. The quality of the casting was examined by visual inspection, optical microscopy, ultrasonic and X-ray tests. From the results obtained, it was evident that CS-RE-PC mould set-up or design was most suitable with a runner system for four-cavity application. This design exhibited best flow rate, as a nearly defect-free casting component was produced. Comparison of the FLOW 3D simulation results with similar experimental findings provided potential opportunity to reduce both cast product rejection rate and rework, and consequently it aids enhancement of the productivity and profitability in a manufacturing/casting industry.

Hydroxyapatite (HAP) is the naturally occurring mineral form of calcium apatite and the most studied material as a bone substituent. Considering HAP's inherent properties, this study explored changes in HAP's characteristics from doping with other metals such as Fe. To form pure HAP and Fe-HAP with different amounts of Fe, we used the hydrothermal approach, and the composites that formed were thoroughly analyzed for their crystallinity, surface bonding, morphology, magnetic behavior, mechanical strength, biocompatibility, hemocompatibility, and in vitro cytotoxicity. The powder XRD studies confirmed the samples' crystallinity, and the lowest crystalline size was 19.7 nm in 10Fe-HAP. The FTIR analysis confirmed the formation of HAP by the hydroxyl, phosphate, and carbonate groups. The FESEM demonstrated that the morphology of the pure HAP was rod-shaped, which transformed into spheres after Fe doping. The EDS analysis confirmed the successful formation of HAP and Fe-HAP composites. The magnetic studies indicated the diamagnetic behavior of the pure HAP, while the Fe-doped HAPs had a superparamagnetic nature with saturation magnetizations (Ms) of 2Fe-HAP, 4Fe-HAP, and 10Fe-HAP at 0.0062, 0.0092, and 0.029 emu/g respectively. Assessment of the mechanical properties, biocompatibility, hemocompatibility, and cytotoxicity indicated that the Fe-doped HAPs were superior to the pure HAP, and among the Fe-HAPs, the 10Fe-HAP) had the highest amount of Fe and the best characteristics. The studies also indicated that Ca2+ interactions influenced the cells via HAP doping with that of Fe, equally increasing the physicochemical and biological properties.

Ruthenium and copper nanoparticles were incorporated into MCM-41-like mesoporous silica via a fast sol-gel method at 80 °C using rice husk ash (RHA) as the silica source. The physico-chemical characterization of the synthesized materials was carried out using various analytical techniques. The X-ray diffraction results indicated that the mesoporous silica synthesized in this study had the standard MCM-41 structure. The Fourier transform infrared spectroscopy results showed that ruthenium and copper ions were successfully incorporated into the hexagonal framework of the mesoporous materials. The transmission electron microscopy results revealed that the RHA-MCM-41, MCM-41-10Ru, and MCM-41-10Ru10Cu samples consisted of ordered mesoporous straight channels. MCM-41-10Cu consisted of copper nanospheres. MCM-41-10Ru and MCM-41-10Ru10Cu showed ruthenium nanoparticle agglomerates distributed on their external MCM-41 framework surfaces. In the case of MCM-41-10Cu and MCM-41-10Ru10Cu, copper ions were homogeneously dispersed on the internal surface of the agglomerated porous silica matrix. The as-prepared Ru- and Cu-doped MCM-41 catalyst was used for the acetylation of glycerol. The catalyst showed a high conversion of 98% and high shape selectivity towards the formation of diacetin and triacetin unlike conventional silica-based catalysts, which show selectivity towards the formation of monoacetin.

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.

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.

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.

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.

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.

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.

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 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.

Application of ionic liquids (ILs) and their polymers (PILs) as green chemicals in the petroleum industry is an original area of the research study. This work aims to synthesize new amphiphilic ILs based on dialkyl substituted imidazolium cations as a head groups combine with acetate and 4-(trifluoromethoxy) phenyl borate anions. Their surface activity and aggregation behaviors, in toluene and aqueous medium, have been investigated by surface tension, particle size distribution and zeta potentials measurements. The sizes of aggregates in water and toluene solvents have been investigated from the dynamic light scattering (DLS) measurements. The demulsification mechanism for the heavy crude oil/water emulsions at low water contents has been estimated from the fluorescent optical microscope in the presence of the prepared ILs and PILs. The demulsification performance of ILs and PILs demulsifiers was found to be considerably improved with incorporation of oxyethylene units into hydrophobic imidazolium cations, and increment the content of 4-(trifluoromethoxy)phenyl borate anions. The results confirmed that the PIL has stronger adsorption for asphaltene molecules facilitated the distortion of the asphaltene protective film that stabilized the water-in-oil emulsion and thus promoting the water droplets coalescence to realize the separation of water from oil.

Amphiphilic materials based on natural products and biomaterials attracted great attention to replace the petroleum based oil field chemicals as environmentally and ecofriendly materials. The present study modified and characterized the chemical structure of cardanol produced from cashew nut oil with amines and glycols to produce new ionic surfactants. The surface and interfacial activities of the prepared nonionic cardanol surfactants were investigated to study their adsorption at water and oil surfaces. The ability of the cardanol surfactants to act as asphaltene dispersant and water in crude oil emulsion breaker for heavy crude oil were evaluated and showed good results as single surfactant to acts as dispersant and demulsifier for heavy crude.

Cobalt ferrite nanoparticles are synthesized using biological agents as fuel by both conventional and microwave heating methods. We focused on the green synthesis of cobalt ferrite, which is eco friendly, inexpensive, and easy to produce by large-scale synthesis. Synthesis methods were carried out under the same conditions. The role of the plant extract and advantages of microwave techniques are discussed. Plant extract-mediated nanoparticles were characterized by various techniques to analyze the size, shape, crystallinity, optical, magnetic, and antimicrobial properties. The X-ray diffraction pattern revealed single-phase crystalline structures with an average size of 45–55 nm. The functional groups present in the samples were confirmed by Fourier transform infrared spectroscopy. From SEM and DLS studies, it is confirmed that the spherical nanoparticles range in the size of 300–500 nm for CHM and 5–50 nm for MHM. Energy-dispersive X-ray spectroscopy analysis confirmed the presence of cobalt, iron, and oxygen. The energy band gap of the samples was measured by UV–Visible diffuse reflection spectroscopy. In photoluminescence analysis, the band emission was observed in the visible region. Samples prepared by microwave heating showed better magnetic behavior than those prepared by conventional heating based on vibrating sample magnetometer analysis. The plant extract makes the synthesis of cobalt ferrite nanoparticles a potentially low-cost and ecofriendly remediation method. The synthesized nanoparticles also exhibited excellent antimicrobial activity against bacteria and fungus strains.

A series of urea-immobilized SBA-15 catalysts were synthesized via post grafting method using 3-chloropropyltriethoxysilane (CPTES) as the anchoring agent. The solid catalyst was characterized by PXRD, N 2 adsorption-desorption, FT-IR, elemental analyzer, TEM, CO 2 -TPD and 29 Si CP/MAS NMR. Detailed analysis of the pore size illustrated the mesoporous nature of the immobilized catalyst. The as-prepared catalyst was further evaluated in the Knoevenagel condensation reaction under different reaction conditions. Benzaldehyde was employed in the Knoevenagel condensation reaction with malononitrile. Catalytic results showed that the Urea(4.8)/SBA-15 exhibits high efficacy (98% of yield) for promoting this reaction at 40 °C and in the absence of a solvent. Under the same reaction conditions, acetylacetone led to a lower benzaldehyde conversion of 10%, whereas ethyl cyanoacetate provides up to 88% conversion. The catalyst could be recycled and reused for at least five reaction cycles with slight loss of catalytic activity.

Green synthesis of silver nanoparticles (Ag NPs) using an extract of dried Zingiber officinale (ginger) root as a reducing and capping agent in the presence of microwave irradiation was herein reported for the first time. The formation of symmetrical spheres is confirmed from the UV-Visible spectrum of Ag NPs. Fourier transform infra-red spectroscopy confirms the formation of the Ag NPs. X-ray diffraction analysis was utilized to calculate the crystallite size of Ag NPs and the value was found to be 10nm. High-resolution transmission electron microscopy and high-resolution scanning electron microscopy were used to investigate the morphology and size of the synthesized samples. The sphere like morphology is confirmed from the images. The purity and crystallinity of Ag NPs is confirmed by energy-dispersive X-Ray analysis and selected area electron diffraction respectively. The electrochemical behavior of the synthesized Ag NPs was assessed by cyclic voltammetry (CV) and shows the redox peaks in the potential range of -1.1 to +1.1V. Agar diffusion method is used to examine the antibacterial activity of Ag NPs. For this purpose, two gram positive and two gram negative bacteria were studied. This single step approach was found to be simple, short time, cost-effective, reproducible, and eco-friendly.

Antibiotic drugs are comprehensively used in treating infectious animals, mainly food-producing animals, which may severely affect other living organisms. Hence, it is necessary to develop a device to monitor trace level of these drug in food samples by a sensitive method. Carbon nanomaterials are usually fabricated as a disposable electrode in an electrochemical sensing application; however, its hydrophobicity nature causes poor electrode stability. An effective strategy is followed in this study to improve the aqueous dispersion of vapor-grown carbon fiber (VGCF) materials through the bio-inspired polydopamine (PDA) functionalization approach. The PDA functionalized VGCF (PDA-VGCF) is significantly characterized by spectroscopic and microscopic methods. The improved hydrophilicity of PDA-VGCF composite materials can offer an easy way to prepare catalyst slurry for the coating of a glassy carbon electrode (GCE) and used to determine the chloramphenicol (CAP) antibiotic drug. Interestingly, cyclic and differential pulse voltammetry studies are performed to observe the electrocatalysis of CAP using PDA-VGCF/GCE, displays a good linear response range (0.01–142 µM), lower detection limit (3 nM), and higher sensitivity (0.68 µAµM−1 cm−2) with long-time stability up to 30 days. Furthermore, PDA-VGCF/GCE shows an admirable selectivity while existing with other interference compounds and practical feasibility are also evaluated in apple juice, milk, and honey samples.

Over the past few decades, the use natural products and their derivatives as green chemicals in different applications has been increasing, due to these products’ green character, wide availability, and renewability. Curcumin is a widely available and utilized natural compound, and in this work it was converted to potassium curcuminate, which was made to react with ethoxylated hexadecyl ammonium chloride (EHC) or ethoxylated octadecyl ammonium chloride (EOC) to produce the amphiphilic ionic liquids (AILs) ethoxylated hexadecylammonium curcuminate (EHC-IL) and ethoxylated octadecylammonium curcuminate (EOC-IL), respectively. The chemical structure, surface activity, relative solubility number, thermal stability, and dynamic light scattering of EHC-IL and EOC-IL were determined with different techniques. In addition, their efficiencies in the demulsification of emulsions of water in heavy crude oil were evaluated. Moreover, the factors affecting on the demulsification efficiency, including the effect of AIL concentration, water content, temperature, and salinity were also evaluated. Both compounds displayed high efficiency as demulsifiers with efficiency increasing with the demulsifier concentration, water content, and demulsification temperature. Furthermore, EHC-IL displayed higher efficiency and produced cleaner demulsified water than EOC-IL.

Green oil-field chemicals based on ionic liquids (ILs) are highly recommended as demulsifiers for heavy crude oil emulsions due to their low vapor pressure, high thermal and chemical stability against degradation in harsh processing conditions. Novel multifunctional tricationic pyridinium ionic liquids (TCPyILs) were synthesized by the reaction of cyanuric chloride with tetraethylene glycol followed by its linking with quaternized aminopyridinium bromide using Bis(chloroethyl) ether as a linker. The chemical structures, surface and interfacial activities and thermal stabilities of the prepared pyridinium ILs were investigated. The amphiphilicity, surface and interfacial activity of the prepared TCPyILs recommended their application as chemical additives in petroleum industry. To the best of our knowledge, it is the first time to apply TCPyILs as demulsifiers for W/O emulsions with high stability and low droplet size (around 2 μm). Comparing with traditional monocationic pyridinium ILs, the prepared TCPyILs had higher efficiencies to demulsify W/O emulsions with different Vol %. The effects of alkyl chain lengths, demulsifier doses and RSN values on the demulsification activities were studied. The results indicated that TCPyILs with nonyl and tetradecyl alkyl chains had better and higher demulsification efficiency comparing with those containing hexadecyl alkyl chains. The demulsification efficiencies of TNPy and TTPy ILs for W/O (50/50, 30/70 and 10/90 vol%) reached 100% even at low concentrations.

In the present study, we have evaluated the gas sensing and photocatalytic activity of reduced graphene oxide (rGO) conjugated titanium dioxide (TiO2) nanoparticles (NPs) formed by the hydrothermal method. The as-synthesized rGO-TiO2 nanocomposite were characterized for the physicochemical properties such as the nature of crystallinity, functionalization, and morphology by making use of the powder X-ray diffraction, Fourier transform-infrared spectroscopy, and scanning electron microscopy, respectively. On testing the gas sensing properties, we found that the rGO-TiO2 nanocomposite can serve as the chemoresistive-type sensor because of its sensitivity and selectivity towards different concentrations of hydrogen and oxygen at room temperature conditions. However, the rGO-TiO2 sensor’s response and recovery speed towards hydrogen and oxygen needs further optimization. Test of photocatalytic activity of TiO2-rGO catalyst for the removal of two model contaminant dyes, RhB and MB showed effective removal, with respective degradation percentages of about 80 and 90% within the first 50 min of irradiation under visible light irradiation. Besides, MB was more effectively degraded using TiO2-rGO than pure TiO2 during the first 30 min of irradiation and this enhanced activity can be attributed to the increased capacity of light absorption, the efficiency of charge carriers separation, and the specific surface area maintained by the rGO-TiO2 nanocomposite to effectively utilize the photo-generated holes (h+) and superoxide radicals (O2− ), responsible for the degradation of the dye. Based on the overall analysis, the formation of rGO-TiO2 nanocomposite can significantly improve the gas sensing and photocatalytic properties of TiO2 NPs and thus can be potential for practical applications in future nanotechnology.

We investigated the binding of the cephalosporin-class drug cefoperazone (CFP) with bovine serum albumin (BSA) using spectroscopic techniques and in silico methods. The aim of this study was to (i) emphasize the importance of correcting for the inner filter effect in this type of study and (ii) understand the binding mechanism of CFP with BSA by addressing protein conformation and plausible binding sites. Formation of the complex was confirmed by UV–visible spectroscopy. Quenching of BSA fluorescence in the presence of CFP was also observed. Because of the high absorption of CFP in the fluorescence emission range of BSA, the fluorescence emission spectra were corrected for the inner filter effect. Fluorescence emission was studied at excitation wavelengths of 280 and 295 nm. The uncorrected data showed a significant contribution of tyrosine at the excitation wavelength of 280 nm; however, after correction, this contribution became negligible. The static-type mechanism was found to be involved in quenching, with almost 1:1 binding between BSA and CFP. Hydrogen bonding and hydrophobic forces were found to dominate the protein–ligand interactions with a slight decrease in the α-helical contents. Synchronous fluorescence spectral data (at Δλ = 15 and 60 nm) were also corrected for the inner filter effect, with the results being similar to those of excitation at 280 and 295 nm. Molecular docking and molecular dynamics (MD) simulation results suggest that, apart from the two known drug binding sites (drug site I and II), one putative binding site (binding site III) located between BSA domains 1 and 3 was also possible for CFP. MD simulations of the previously reported drug binding sites (drug site I and II) and putative binding site III revealed that binding site III showed excellent binding profiles and could be a target for future research related to BSA-drug binding.

© 2021 Elsevier Ltd. All rights reserved. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1016/j.conbuildmat.2021.124117

This paper describes the interaction of indomethacin with bovine serum albumin (BSA) using experimental and computational approaches. Inner filter effect (IFE) had significantly impacted the fluorescence results as uncorrected data shown the considerable involvement of tyrosine residues which became very low after correcting the data with the former, thus, only the tryptophan residues were found to be associated with fluorescence quenching. Analyses of the corrected data suggested that there was 1:1 strong binding between BSA and indomethacin that taken place via static quenching mechanism. The binding was exothermic in nature and energetically favorable with ordering of the system. The binding of indomethacin remained almost unchanged in presence of low amount of sodium dodecyl sulfate (SDS) surfactants monomers while it significantly diminished when the concentration of SDS monomers increased. Low concentrations of indomethacin didn’t affect the secondary structure of BSA, however, high concentrations led to the partial unfolding of the protein. Molecular docking along with molecular dynamics simulation results explained that this drug molecule occupied new binding site with strong binding affinity of −8.35 kcal/mol, which is oriented in the interface between domain 1 and domain 2. The interaction was facilitated by both hydrophobic forces as well as hydrogen bonding.

Asphaltene aggregation and flocculation in upstream and downstream industries cause severe problems due to phase separation and asphaltene particle growth. This work aims to esterify tannic acid (TA) at different molar ratios of heptanoyl chloride (HC) 1:3, 1:6, and 1:9, producing species TA-HC3, TA-HC6, and TA-HC9, respectively. The synthesized esters were characterized by Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), and thermal analyses. Their performances as asphaltene dispersants of Arabian heavy crude oil were assessed by dynamic light scattering (DLS), ultraviolet–visible (UV–Vis) spectroscopy, and viscosity measurements. All specimens (TA-HC3, TA-HC6, and TA-HC9) dispersed asphaltene, and their dispersal abilities increased with increasing number of alkyl chains (i.e., TA-HC3 > TA-HC6 > TA-HC9).

In this paper, a novel in-situ preparation method of multipurpose additives based on Cu2O·2Fe3O4 nanocomposite is presented. Cu2O·2Fe3O4 nanocomposites were synthesized in large quantities by a simple and facile one-step co-precipitation method in the presence of poly(ionic liquid). The prepared Cu2O·2Fe3O4 nanomaterials were applied as multipurpose epoxy coating additive to improve its coating performances as marine coatings of steel. The nanocomposites were characterized by FTIR, XRD, SEM, TEM, and DLS techniques. The incorporation of poly (ionic liquid) into Cu2O·2Fe3O4 nanocomposites reduced the particle size, increased the porosity and zeta potential, leading to improve of the adsorption sites and affinity toward interaction with epoxy coatings. The Cu2O·2Fe3O4 nanocomposites improved the adhesion strength, mechanical stability and self—healing characteristic and the flame retardancy with decreasing the total smoke production of epoxy coatings with steel.

In the present study, a unique precursor source and plant extract have been developed for biogenic synthesis of silver nanoparticles (AgNPs) using different silver precursor solutions. Mesoporous-MnO2 nanocomposites (before doping AgNPs in meso-MnO2) were prepared using anon-ionic surfactant (Triton X-100) and the antibacterial activity of the prepared sample was analyzed against various bacterial pathogens. The plant leaf extract of Alternanthera bettzickiana was used as a reducing agent. A fast ultra-sonication-assisted process facilitated the incorporation of AgNPs on mesoporous MnOx. Different type of silver precursor has been used to prepare the biogenic AgNPs for the first time. Particle sizes of AgNPs were obtained below 5–10 nm. Surface area, morphology, crystalline phase, and particle size of the synthesized nanoparticles were characterized by X-ray diffraction (XRD), Brunauer, Emmett, Teller (BET)/Barrett, Joyner, Halenda (BJH)method, Scanning Electron Microscopy (SEM), and high-resolution transmission electron microscopy (HR-TEM) techniques. The antibacterial activity of biogenic AgNPs and AgNPs@meso-MnO2 were tested against gram-positive (Staphylococcus aureus and Streptococcus mutans) and gram-negative (Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa) bacteria using the well diffusion assay. All samples including biogenic AgNPs and AgNPs@meso-MnO2 showed effective inhibition zones against all pathogens and no activity was observed for control and bulk meso-MnO2. Preliminary studies related to the anti-cancer activity of the prepared AgNPs have also been studied and compared for different route prepared silver nanoparticles.

Biogenic silver nanoparticles (AgNPs) have been synthesized by using Solanum tuberosum (potato) extract (PE) as a reducing as well as stabilizing agent which is reasonably cheaper, non-toxic and easily available material. The green synthesis of silver nanoparticles has been carried out by very simple method and the nanoparticles were characterized by surface plasmon band as well as TEM measurements. The PE-AgNPs were highly dispersed in the solution and found to be spherical with around 10nm in size. Interaction of these nanoparticles was studied with plasma protein HSA by means of various spectroscopies, such as, UV-visible, fluorescence, DLS, CD and FTIR spectroscopies. The HSA was found to form the protein "corona" around the starch-capped PE-AgNPs. Absorption spectroscopy revealed that the interaction between HSA and PE-AgNPs resulted in the ground state complex formation. Due to the strong absorption of PE-AgNPs, the inner filter effect was corrected for the fluorescence data. PE-AgNPs were found to quench the fluorescence of HSA with a small blue shift attributed to the increase in the hydrophobicity near tryptophan residue due to the presence of amylopectin and amylose units in the starch. The value of n, Hill's constant, was found to be >1 which determines the existence of a cooperative binding between nanoparticle and albumin. Several parameters such as Stern-Volmer and binding constants in addition to the thermodynamic parameters have been analyzed and discussed which established that the complex formation has taken place via static quenching mechanism and the corona formation between albumin and PE-AgNPs was entropy driven process. Binding of biogenic PE-AgNPs to the HSA slightly affected the secondary structure of latter with a small decrease in α-helical contents resulting in the partial unfolding of the protein, though the structural motif remained the same. Molecular docking simulations revealed various possible binding modes between PE-AgNPs and albumin.

Herein, we report a sustainable production of magnetic cobalt ferrite nanoparticles by conventional (CHM) and microwave heating (MHM) method. Hibiscus rosa-sinensis extract was used as both reducing and stabilizing agent. Using plant extracts to synthesize nanoparticles has been considered as an eco-friendly method, since it avoids noxious chemicals. The plethora of plant extract mediated nanoparticles were compared by techniques, such as XRD, Rietveld, FT-IR, SEM, EDX, UV-Visible DRS, PL and VSM were carried out to analyze and understand their crystallite size, functional groups, morphology, optical and magnetic properties. The crystalline structure of cobalt ferrite nanoparticles revealed the cubic structure and the microwave heating of nanoparticles showed smaller crystallite size compared to the conventional heating, which was then confirmed by XRD analysis. To analyze the presence of functional groups and the phytochemical involvement of the plant extract was confirmed by FT-IR studies. Spherical morphology with less than 100 nm sized particles was confirmed by SEM and EDX analysis confirm the existence of Co, O, and Fe elements present in the samples. UV-Visible DRS studies were carried out to calculate the band gap of the as-synthesized nanoparticles, estimated from the Kubelka-Munk function, as 2.06, and 1.87 eV for CHM and MHM, respectively. Photoluminescence emission spectrum of the nanoparticles showed two different bands at 494 and 620 nm, which explores the optical properties of the nanoparticles, due to the quantum confinement effect. VSM analysis showed better ferromagnetic behavior, which can be used for magnetic applications.

In this, we developed superparamagnetic iron oxide nanoparticles (SPIONs) to be appropriate for the diagnosis and treatment of cancer cells by means of magnetic resonance imaging (MRI) and magnetically controlled hyperthermia/drug delivery (respectively). For the preparation of composite, we started with SPIONs, followed by its coating with gold to form SPIONs@Au, which further conjugated with luteinizing hormone-releasing hormone (LHRH) protein by making use of the cysteamine (Cyst) space linker and finally loaded with 5-Fluororacil (5-Fu) anticancer drug to form SPIONs@Au-Cyst-LHRH_5-Fu composite. Thus formed composite was thoroughly characterized by making use of the instrumental analysis such as HRTEM, EDAX, DLS, TGA, XPS, UV-vis, FTIR, HPLC and SQUID magnetics. We found from the analysis that the particles are spherical in shape, monodispersed with a size distribution of around 6.9nm in powdered dry form, while in solution phase it is 8.7nm. The UV-vis, FTIR, and HPLC studies confirmed for the loading of the 5-Fu drug onto the surface of SPIONs core and the maximum amount of drug that got adsorbed to be about 42%. The SQUID magnetic studies provided the information for the superparamagnetic behavior of the drug loaded SPIONs and the saturation magnetization (Ms) values observed to be about 11emu/g and the blocking temperature (TB) of 348K. On testing the particles to see the effects of magnetic fluid hyperthermia (MFH) due to some changes in the solvent medium and oscillating frequency, the material seems to be highly active in aqueous medium and the activity gets increased with respect to the applied frequency of oscillation (430Hz>230Hz>44Hz). From the heat release studies, the calculated specific power loss (SPL) values for the SPIONs@Au-Cyst-LHRH_5-Fu composite are at the highest of 1068W/g in water (430Hz) vs the least of 68W/g in toluene (44Hz). Further, the drug release studies tested under the influence of magnetic field provided the information that the composite released its entire loaded drug following an exposure to the magnetic field (430Hz over 4h time), while only 53% (over 5h) for the controlled measurements of no magnetic field, thereby supporting to have the magnetic field so as to observe the externally controlled drug release effects. Finally, the results of the study provide the information that the SPIONs@Au-Cyst-LHRH_5-Fu composite can be potential for theranostic applications of cancer through the phenomenon of applying for MRI, magnetically controlled hyperthermia and drug delivery externally.