Sutherlandjamison8370

To investigate the binding characteristics of the ligands with the σ2 receptor, a 3D homology model was developed. To understand the binding pattern of the γ-butyrolactone and oxazolidinone based ligands, molecular docking studies were performed on both σ1 and σ2 receptors. Furthermore, MM/GBSA binding energy calculations were used to confirm the binding of ligands on the σ2 over σ1 receptor. These in silico findings will aid in the discovery of selective σ2 ligands with good pharmacophoric properties and potency in the future.Photoluminescent carbon dots (CDs) possess several advantages, which include high stability and a non-toxicity that are essential in different applications such as catalysis, drug delivery, and sensors. The presence of heteroatoms modifies their physicochemical characteristics. In this work, a combination of CDs is manufactured utilizing a solvothermal technique using citric acid and thiourea. After separating each section using column chromatography, green and yellow CDs with average diameters of 8.3 and 7.0 nm, respectively, are generated. Next, optical and structural characterizations indicated that the variation in the emission color was caused by differences in surface functional groups rather than particle size. The photoelectrochemical properties are explored by including quinone derivatives and metal ions, which are quenchers for the CDs. The photoluminescence quenching results showed the presence of anionic functional groups on the surface of the CDs. Furthermore, these functional groups interacted strongly with particular types of metal ions, indicating that they may be employed as metal ion sensors.The significance of reliable monitoring of uranium levels in water recourses calls for the development of time-saving, robust, and accurate methods for its estimation. In this view, the current study describes the design and analytical parameters of a potentiometric membrane sensor for uranium(vi) ions. The sensor is based on a new Schiff base derivative, as an ionophore, that was synthesized and structurally characterized by elemental, FTIR, and 1HNMR analyses. The impact of the membrane constituents was studied and the membrane composition of PVC (32.50)  o-NPOE (65.00)  ionophore (2.00)   KTpClPB (0.50) (%, w/w) achieved the optimal performance. A Nernestian response was observed for uranium(vi) ions within the concentration range 1.00 × 10-6 to 1.00 × 10-1 mol L-1. The sensor revealed a low detection limit of 3.90 × 10-7 mol L-1 with satisfactory reproducibility. Stable and reproducible potentials were obtained within a short time (9 s) over the pH range 2.10-4.21. The impact of possible competing ions was investigated and the selectivity coefficients revealed appropriate selectivity for uranium(vi) ions over various cations without significant interference. The sensor's performance was examined by determining the amount of uranium(vi) in water samples and the results showed no significant differences from those obtained by the ICP-OES method.Biliverdin IX-alpha (BV), a tetrapyrrole, is found ubiquitously in most living organisms. It functions as a metabolite, pigment, and signaling compound. While BV is known to bind to diverse protein families such as heme-metabolizing enzymes and phytochromes, not many BV-bound lipocalins (ubiquitous, small lipid-binding proteins) have been studied. The molecular basis of binding and conformational selectivity of BV in lipocalins remains unexplained. Sandercyanin (SFP)-BV complex is a blue lipocalin protein present in the mucus of the Canadian walleye (Stizostedion vitreum). In this study, we present the structures and binding modes of BV to SFP. Using a combination of designed site-directed mutations, X-ray crystallography, UV/VIS, and resonance Raman spectroscopy, we have identified multiple conformations of BV that are stabilized in the binding pocket of SFP. In complex with the protein, these conformers generate varied spectroscopic signatures both in their absorption and fluorescence spectra. We show that despite no covalent anchor, structural heterogeneity of the chromophore is primarily driven by the D-ring pyrrole of BV. Our work shows how conformational promiscuity of BV is correlated to the rearrangement of amino acids in the protein matrix leading to modulation of spectral properties.Surface treatment is known as a very efficient measure by which to modulate the surface properties of biomaterials in terms of grain structure, topography, roughness and chemistry to determine the osseointegration of implants. In this work, a two-step method of surface modification was employed to impart high osteogenic activity and biomineralization capacity on a Ti-25Nb-3Mo-2Sn-3Zr alloy (a type of β-titanium named TLM). The preliminary surface mechanical attrition treatment (SMAT) refined the average grain size from 170 ± 19 μm to 74 ± 8 nm in the TLM surface layer and promoted the surface to be much rougher and more hydrophilic. The subsequent Ca-ion implantation did not change the surface roughness and topography obviously, but enhanced the surface wettability of the SMAT-treated TLM alloy. The in vitro evaluations of the adhesion, proliferation, osteogenic genes (RUNX2, ALP, BMP-2, OPN, OCN and COL-I) and protein (ALP, OPN, OCN and COL-I) expressions, as well as extracellular matrix (ECM) mineralizationoutstanding osteogenic and biomineralization properties, providing a potential means for its future use in the orthopedic field.A new approach has been developed for environmentally friendly C-C cross-coupling reactions using bi-functional Pd(ii)-salen complex-embedded cellulose filter paper (FP@Si-PdII-Salen-[IM]OH). A Pd(ii)-salen complex bearing imidazolium [OH]-moieties was covalently embedded into a plain filter paper, then used as an efficient portable catalyst for the Heck, Suzuki, and Sonogashira cross-coupling reactions under environmentally friendly conditions via the filtration method. The catalytic filter paper properties were studied by EDX, XPS, TGA, ATR, XRD, and FESEM analyses. The reactions were catalyzed during reactants' filtration over the catalytic filter paper. The modified filter paper was set up over a funnel and the reactants were passed through the catalytic filter paper several times. The effect of reaction parameters including loading of Pd(ii)-salen complex, temperature, solvent, and contact time were carefully studied and also the optimal model of conditions was presented by the design expert software. High to excellent yields were obtained for all C-C coupling types with 5 to 8 filtration times. Under optimal conditions, all coupling reactions showed high selectivity and efficiency. Another advantage of the modified filter paper was its stability and reusability for several times with preservation of catalytic activity and swellability.The molecular weight of collagen-degrading polypeptides (CDPs) extracted using the alkali method from leather scraps must be expanded to improve its utilization effect. A novel polymer (CPP) was synthesized from tricyanogen chloride (TC) and CDP by mechanical force without water. According to the solution viscosity and content of water-soluble matter, the optimal condensation conditions of the n(TC)/n(CDP) and temperature were obtained and the properties of CPP, such as the molecular weight, thermal properties, and isoelectric point were tested and analyzed. The synthesis of CPP was simulated by the substitution of l-threonine containing hydroxyl and amino groups for the condensation reaction of CDP and TC. The result illustrated that only amino groups were involved in the substitution of chlorine accomplished by the SN2 pathway. Based on this, a probable formation mechanism of CPP was proposed. As an illustration, CPP has good utilization values in the preparation of a corrugated paper jelly instead of gelatin. The preparation of polypeptide water-based adhesive by a mechanochemical method not only has good controllability in the production process but also can save water and energy.Cu2O spherulites are solvothermaly fabricated by using Cu(NO3)2 as the starting material and polyvinylpyrrolidone (PVP) as a multifunctional growth agent. The specimens at different growth stages are investigated by using X-ray diffraction, electron microscopy, energy dispersive X-ray spectroscopy, soft X-ray emission spectroscopy and infrared spectroscopy. The formation mechanism of Cu2O spherulites is proposed accordingly. Hierarchically, the spherulites are composed of needle-like submicron-rods lying along the radial orientations. The submicron-rods are constructed by piling up of small Cu2O/PVP spheres. The embedded Cu2O nanocrystallites can generate a dipolar field in each along the [100] direction. They deposit at the surface of a negatively charged PVP-containing spherical core, and self-oriented along the radial directions. IACS-10759 chemical structure Therefore, all the Cu2O nanocrystallites would have their positively charged (100) facet facing to the core and their negatively charged (1̄00) facet turning towards to the spherulite surface, leading to a negatively charged surface of spherulites. Unlike randomly oriented nanocrystallites embedded in polymer microspheres, the spherulites would not undergo surface recrystallisation into a single crystal shell due to the restricted potential of local shift and rotation of the nanocrystallites by the Coulomb force from the core. This work provides new perspective towards the formation of spherulites and their structural properties.Gas hydrate has great application potential in gas separation, energy storage, seawater desalination, etc. However, the intensity of mass and heat transfer is not enough to meet the needs of efficient hydrate synthesis. Nanoparticles, different from other liquid chemical additives, are considered as effective additives to promote hydrate formation due to their rich specific surface area and excellent thermal conductivity. This work summarizes the effect of the nanoparticles on the thermodynamics and kinetics of hydrate formation. And also, this work probes into the mechanism of the effect of the nanoparticles on the formation of hydrate as well as provides some suggestions for future research. It is found that it's difficult for nanoparticles to effectively promote the formation of the gas hydrate without the use of surfactants, because the adhesion characteristics of the nanoparticles make them easily agglomerate or even agglomerate in solution. In addition, at present, the research on the influence of nanoparticles on the formation and decomposition of natural gas hydrate is still very fragmented, and the micro mechanism of the influence is not clear, which requires more systematic and specific research in the future. At the same time, the development of nanoparticles that can promote the formation of natural gas hydrate should also become the focus of future research.Various diboronic acid-based chemosensors for d-glucose have been developed for use in diabetes diagnostic systems. However, most of these chemosensors have limitations, such as poor water solubility, difficulties in synthesis, and inability to selectively detect d-glucose from among other saccharides. We report a simple chemosensor based on a supramolecular complex of fluorophenylboronic acid-appended β-cyclodextrin (FPB-βCyD) and an anthracene-based probe having a boronic acid moiety (1). Hydrophobic 1 is encapsulated in the cyclodextrin cavity of FPB-βCyD, making the supramolecular complex (1/FPB-βCyD) applicable in a water-rich solvent mixture (98% water). Interestingly, 1/FPB-βCyD showed a strong turn-on response to d-glucose with a 9.6-fold enhancement in fluorescence intensity, and no response to other saccharides. This study uncovers an innovative approach based on the supramolecular assembly of simple components for the development of a water-soluble d-glucose chemosensor with excellent selectivity.