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This work characterizes microemulsions of Medicago marina essential oil and evaluates their antimicrobial, antibiofilm, and anticoagulant effects. Medicago marina L. aerial parts essential oil was hydro-distilled and analyzed by gas chromatography-FID and gas chromatography/mass spectrometry (GC/MS) for the first time from the Tunisian chemotype. The microemulsion was prepared using an oil/water formulation with a biopolymer (Arabic gum) and surfactant (Tween 20). Antibacterial and antifungal activities were evaluated using the microbroth dilution method, while anticoagulant activity was tested in vitro using prothrombin time (PT) and aPTT tests. Eventually, the binding affinities and molecule’s interactions of the main chemicals with the operational locations of C (30) carotenoid dehydrosqualene synthase and cytidine deaminase were explored. The essential oil contained 71 compounds of which 87.6% were identified. Major compounds were $\beta$-ionone (17.67%), 1-methyleugenol (10.75%), eugenol (8.86%), $\beta$-damascenone (4.33%), and $\alpha$-humulene (4.32%). A microemulsion with a diameter of 1.63 $\mu$ m, a polydispersity index of 0.17, a zeta potential of –40.8 mV and a pH of 6 was obtained and it showed the highest antibacterial potential against a multitude of microbes, with low MICs varying between 0.406 mg/mL and 3.25 mg/mL. Significant antibiofilm activity was observed with over 80% inhibition at 4 × MIC concentration. It showed better anticoagulant activity than heparin, with PT and aPTT values of 19.5 s and 57 s, respectively, at 10 mg/mL. Molecular docking showed that “($E)$-$\beta$-ionone” had the highest binding scores. Notable pharmacokinetic and drug-like qualities were found in the obtained molecules after establishing ADME profiling. As a result, Medicago marina L. Essential oil microemulsion can be used in food processing as a preservative.

Electronic absorption spectroscopy was used to measure the molecular association of copper phthalocyanine tetrasulfonate in micellar solutions, a microemulsion made with cationic surfactant, and homogeneous solvents. Analysis of absorbance versus concentration data using a multiple-aggregation model and non-linear regression analysis gave values of association constants, molar absorptivities and estimates of average aggregation number. Microemulsions and aqueous micellar solutions made with alkylammonium surfactants inhibited aggregation, probably because of interactions between the phthalocyanine sulfonate groups and the cationic surfactant head groups at interfacial surfaces. Similar aggregation behavior was observed previously in multiple-bilayer films of cationic surfactants. Water and aqueous solutions containing tetraethylammonium bromide or anionic SDS micelles provide environments facilitating extensive aggregation of Cu^IIPcTS⁴⁻. The major species are dimers in water and acetonitrile/water, but the formation of higher aggregates is promoted by addition of SDS or TEAB. Aprotic organic solvents provide environments intermediate between these two extremes, giving relatively large aggregation numbers (i.e. five to seven) but smaller association constants than aqueous media not containing cationic surfactants.

Tanshinone IIA (TanIIA) has neuroprotective effects against cerebral ischemia reperfusion injury (CIRI), but its clinical application is limited due to poor water solubility and robust first pass elimination property. In this study, we developed microemulsion loaded with TanIIA (TanIIA ME) to break through these limitations, and explored the neuroprotective effect of TanIIA ME against CIRI and the epigenetic regulation mechanism of this neuroprotection. In vivo, middle cerebral artery occlusion (MCAO) models were treated with TanIIA ME and TanIIA solution or sodium valproate as a control. The effect of TanIIA ME on HDAC activity was determined by ELISA assay. In addition, we used primary hippocampal neurons to establish oxygen-glucose deprivation and reoxygenation (OGD/R) models. Lactate dehydrogenase (LDH) assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were performed to investigate the neuroprotective efficacy of TanIIA ME. Subsequently, the expression of H3K18ac, H4K8ac, NMDAR1, caspase-3, and MAP-2 were investigated in MCAO or OGD/R models treated with TanIIA ME, TanIIA solution or sodium valproate. In vivo experimental results indicated that TanIIA ME significantly reduced neurological scores, infarction volume, and HDAC activity compared with TanIIA solution and MCAO group, accompanied by upregulation of H3K18ac, H4K8ac, and MAP-2 expression and downregulation of NMDAR1 and caspase-3 expression. Additionally, in OGD/R models, the results demonstrated that TanIIA ME treatment had a better neuroprotective effect along with increased H3K18ac, H4K8ac, and MAP-2 expression and decreased NMDAR1 and caspase-3 expression, compared with the other treatments except sodium valproate. Overall, TanIIA ME treatment exhibited superior efficacy in protecting against CIRI through mechanisms that might involve the inhibition of NMDAR1 and caspase-3 expression and the enhancement of MAP-2 expression by regulating histone H3K18 and H4K8 acetylation. Thus, TanIIA ME could be potentially used to develop a promising drug for the treatment of ischemic stroke.

Wurtzite ZnO nanomaterials including nanoparticles, nanocolumns and nanorods were successfully synthesized by a solution route. Concentrations of modifying reagent and differences of solvent employed in the synthetic process can effectively adjust the morphologies of the as-grown products. Photoluminescence measurements of the ZnO nanocolumns and nanorods have been carried out at room temperature. A sharp Ultraviolet emission at 386 nm and a weak visible emission centered at 515 nm were observed in the PL spectrum of the nanocolumns, while a UV emission of the nanorods was observed at 377 nm.

Iron nanoparticles dispersed in hydraulic oil were prepared by mixing two microemulsions containing iron (II) sulfate and sodium borohydride at a temperature of 60°C. Six values of ω₀ = [water]/[surfactant] were used, namely 5, 10, 15, 20, 25, and 30. Dynamic light scattering measurements of the hydrodynamic radius of the reverse micelles showed that the average size, surfactant shell thickness and water core radius, increased with ω₀. The micelle size distribution for ω₀ values of 5, 10, and 15, was in the nanometer regime, while for ω₀ values of 20, 25, and 30 it was in the micrometer regime. Scanning electron microscopy showed that the nanoparticle diameters were around 30 nm for the powders prepared using an ω₀ = 10. In addition, a comparison between the particle size distribution of the iron nanoparticles dispersed in isopropyl alcohol and the iron nanoparticles in the reverse micellar solution was made. It was shown that once the particles are cleaned and separated from the micellar solution, they agglomerate into particles that are about 1 μm in size.

In this paper, we systematically drew a series of inverse-microemulsion quasi-ternary system phase diagrams of OP-10+C₈H₁₇OH+C₆H₁₂+brine (CaCl₂/BaCl₂) by adjusting the ratio of CaCl₂ and BaCl₂. On this basis, microemulsions have been prepared with seven different molar ratios of Ca²⁺/Ba²⁺, and calcium carbonate and barium carbonate coprecipitation products were obtained by reaction with an equimolar amount of sodium carbonate. The influence of barium ion to morphology and composition of nanometer calcium carbonate were studied. These samples were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The SEM photographs indicated that when the content of Ca²⁺ was higher, some incomplete large cube of coprecipitation particles were formed in solution, but with the content of Ba²⁺ increased gradually, they formed a large number of small spherical particles, with the further increase of Ba²⁺ concentration, the particles mainly had structures of irregular polyhedron eventually. The measurement results of FTIR and XRD indicated that CaCO₃ coprecipitation products gradually changed from calcite to the vaterite, eventually turned into being aragonite with the further increase of Ba²⁺ concentration.

Cube-shaped CdS nanoparticles have been successfully prepared by a sonochemical method in an oil-in-water microemulsion. The product was characterized by using techniques including X-ray powder diffraction, high-resolution transmission electron microscopy, energy-dispersive X-ray analysis and UV-visible absorption spectroscopy. This microemulsion system in the presence of high-intensity ultrasound irradiation provides special conditions for the nucleation and growth of the CdS nanoparticles.

The shape and size control of barium compound nanoparticles (barium chromate, barium sulfate, barium carbonate) was examined using the water-in-oil microemulsion as nanometer-sized reaction medium. The barium compound nanoparticles were synthesized using the microemulsion formed by AOT as an anionic surfactant and iso-octane as an organic solvent. Chromate, sulfate, or carbonate-containing microemulsion solution and Ba(AOT)₂ reverse micelle solution were mixed. After a few days, the morphology of the product material was observed using TEM. Then, bundle of the nanowire, chain structure of the nanorod, superlattice structure of the nanodot, and dispersed nanodot were synthesized by changing material concentration and material molar ratio. It has been shown that the aspect ratio of the generated particles decreased with increase in the anionic ion concentration. In contrast, the aspect ratio did not change even if the barium ion concentration changed. The surfactant AOT has selectively adsorbed on the specific crystal faces and suppressed their crystal growth. And, the generated particles were self-organized by the hydrophobic interaction of hydrophobic group of the AOT molecule adsorbed onto the particle. In conclusion, it was clarified that the supersaturation ratio and the particle–surfactant interaction were important factors for controlling the shape and size of the inorganic nanoparticles.

The gill mucosa is a convenient route for the administration of DNA vaccine to fish and other aquatic organisms. Nanocarriers have been considered for delivery; however, a suitable formulation is required. To devise an appropriate carrier, we have synthesized chitosan nanoparticles entrapping pDNA at N/P ratios of 1:1 and 2.5:1, using ionic gelation and microemulsion (μE) methods. For nanoparticle characterization, the size, morphology, zetapotential, and IR spectra were determined. The efficiency of pDNA entrapment was established by gel retardation assay. On the basis of the investigations, the loaded nanoparticles synthesized by μE method appear to have the required characteristics for effective delivery by this route.

Various pyrimidine derivatives are well known for their different pharmaceutical applications. The n-butyl 4-(3, 4-dimethoxyphenyl)-6-methyl-2-thioxo-1,2,3,4 tetrahydropyrimidine-5-carboxylate (n-butyl THPM) was synthesized by using n-butylacetoacetate. The n-butyl acetoacetate was obtained by transesterification of ethyl acetoacetate with n-butyl alcohol using Biginelli condensation. The synthesized powder was used to obtain the nanoparticles of n-butyl THPM by using water/oil microemulsion technique. The average particle size was calculated from the powder XRD pattern by applying Scherrer's formula. The nanoparticles of n-butyl THPM were observed by Transmission Electron Microscope (TEM). The diameter of the nanoparticles varied from 15 nm to 65 nm. The nanoparticles were also characterized by FT–IR spectroscopy, TG–DTA–DSC and mass spectroscopy. The n-butyl THPM nanoparticles were stable up to 280°C. Thermodynamic and kinetic parameters of decomposition were obtained by applying Coats and Redfern relation to the thermogram. The dielectric study was carried out in the frequency range of 50 Hz to 5 MHz. The dielectric constant, dielectric loss and ac conductivity decreased as the frequency of applied field increased.

This study aimed to formulate and physically characterized clotrimazole microemulsions and microemulsion based-gels compared with their blank counterparts. Microemulsions were prepared by simple mixing of isopropyl palmitate, 2:1 mixture of water and isopropyl alcohol and 1:1 mixture of polyethylene 20 sorbitan monooleate and sorbitan monooleate. To develop microemulsion-based gels, fumed silica was use as a thickening agent at 2.5, 5 or 7.5% w/w. All studied formulations, i.e., 2 microemulsions and 6 microemulsion based-gels were investigated for physical properties such as appearance, conductivity, pH, rheological behavior and spreadability. Afterwards, 2 microemulsions (ME1 and ME2) and 2 microemulsion based-gels (MBG1-3 and MBG2-2) were selected to incorporate with clotrimazole and then investigated for physical properties. All formulations showed good appearance and physical properties. Clotrimazole did not affect most characteristics of their blank counterparts, except conductivity. Therefore, the investigated microemulsions and microemulsion based gels could be used as the vehicles of clotrimazole for skin drug delivery.

Various methods for the synthesis of copper nanoparticles employing chemical, physical and biological techniques considering bottom-up and top-down methods synthesis have been studied. The properties of copper nanoparticles depend largely on their synthesis procedures. The results from various investigations performed by different scientists using these methods have been summarized. The applications, characterization techniques, advantages and disadvantages of each synthesis method are also the point of discussion. A detailed study of the results reveals that chemical reduction methods are most suitable for the synthesis of copper nanoparticles. Chemical reduction of copper salts using ascorbic acid (Vitamin C) is a new and green approach in which ascorbic acid is used both as the reduction and capping agent. This approach is the most effective and is also economical. Wide applications have been reported in various fields, including heat transfer, catalyst production, electronics and medicine at a commercial scale. This process is nontoxic, environment-friendly and economical. The applications, characterization techniques, advantages and disadvantages of each synthesis method have been presented.

In the water-in-oil (W/O) microemulsions based on anionic (AOT) surfactants, the ω value (molar ratio of water to surfactant), precursor, and surfactant could remarkably affect the synthesis of CuO-ZrO₂ nanocomposite and the morphologies of the sol-gel products simultaneously. In this study, CuO-ZrO₂ nanoparticles are synthesized using microreactors made of surfactant/water/n-hexane microemulsions and discusses the effect of different microemulsion variables on the particle size and particle size distribution by water-to-surfactant molar ratio. The obtained powders are characterized by DTA, XRD, SEM, EDS, and TEM and their physical properties are compared. For AOT surfactant the particle size increased with increasing the water to surfactant molar ratio. The particles size of CuO-ZrO₂ nanocomposite in sample with anionic surfactant with molar ratio of 6 that calcined at 600°C is between 15-20 nm.

Decavanadate is a polyoxometalate consisting of 10 octahedral vanadium centers, which has been found to exert biological effects and has been observed in vivo. Biological activity implies that a material is taken up into a cell or that the material interacts with membrane receptors. Because of the large size and the high molecular charge, it is nontrivial to anticipate how such a large anion interacts with membranes and whether it will be taken up by cells. Therefore, it becomes important to investigate how the anion interacts with membranes and membrane model systems. Since ion pairing is important for the interaction of this large complex with any membrane interface system, we investigate both the nature of Coulombic and neutral noncovalent interactions with membrane model interface systems and cellular systems. Specifically, we used microemulsions as model systems, and in the specific phase diagram regime where reverse micelles form. We find that, there is a large difference in the interaction with different interfaces, and that charge can have an important role. The negatively charged interface repels the anion, whereas a positive interface attracts the anion. However, the interface with neutral surfactant head groups also is found to repel the decavanadate. This result demonstrates that the discrete charge Coulombic interactions are not the only forces in effect, and that the interactions are at least to a first approximation dictated by the interface charge and not by the counterions in the system. Alternative forces include van der Waals attraction, pH of the water pool, and field and surface effects. Because biological membranes have differently charged ligands, it is not clear which interface systems provide the best analogy with cell surfaces. However, surface charge may affect the compounds and facilitate the interactions that could be important. For example, a positively charged surface could potentially facilitate hydrolysis and sequential abstraction of one or two vanadium atoms at a time from decavanadate. Recently, decavanadate was used as a structural model for the V₂O₅ material. Negatively charged interfaces have also been found to accelerate compound hydrolysis or in other ways alter reactions in compounds near the interface. Lipid-like interfaces potentially contribute to processing of coordination compounds. Decavanadate has been found to interact with proteins and insulin enhancing effects have been reported. Interactions with coordination compounds and the mechanisms of interactions should continue to be investigated because such systems may reveal the mode of interaction of these compounds.

Cube-shaped CdS nanoparticles have been successfully prepared by a sonochemical method in an oil-in-water microemulsion. The product was characterized by using techniques including X-ray powder diffraction, high-resolution transmission electron microscopy, energy-dispersive X-ray analysis and UV-visible absorption spectroscopy. This microemulsion system in the presence of high-intensity ultrasound irradiation provides special conditions for the nucleation and growth of the CdS nanoparticles.