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European Journal of Pharmaceutics and... Jun 2024The solidification of deep eutectic solvent (DES) through wet impregnation techniques on inert solid carriers is an interesting approach that offers better processing...
The solidification of deep eutectic solvent (DES) through wet impregnation techniques on inert solid carriers is an interesting approach that offers better processing attributes and excellent stability. Herein, DES of Fimasartan (FS) was developed to improve its solubility and bioavailability. The selected DES-FS was solidified by wet impregnation method employing Nesulin US2 and Aerosil 200. The SeDeM-SLA (solid-liquid adsorption) system was employed to investigate flow attributes of solidified DES-FS. Further, the selected solidified DES-FS (A) was characterized by Fourier transforms infrared spectroscopy (FTIR), Powder X-ray diffraction (PXRD), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM). The DES comprising Choline Chloride (ChCl): Glycerol (Gly) (1:3) revealed maximum drug solubility (35.6 ± 2.2 mg/mL) and thus opted for solidification. Solidification through wet impregnation was employed using 1:0.5 ratios (DES-FS to carriers). The Index of Good Flow (IGF) value was calculated from the SeDeM-SLA expert system, which indicates the better flow characteristics of solidified DES-FS, particularly with Neusilin US2 [SDES-FS (A)]. The solid-state evaluation data of SDS-FS (A) suggested a transition of FS to an amorphous form, resulting in an increment in solubility and dissolution. A similar trend was reported in the in vivo pharmacokinetic study, which indicated a 2.9 folds increment in the oral bioavailability of FS. Furthermore, excellent stability, i.e., a shelf life of 28.44 months, reported by SDES-FS (A) in accelerated stability studies, suggests better formulation perspectives. In a nutshell, the present study evokes the potentiality of performing solidification through wet impregnation and successful implementation of the SeDeM-SLA expert model, which could find wide applications in pharmaceutical science.
PubMed: 38917948
DOI: 10.1016/j.ejpb.2024.114381 -
Journal of Synchrotron Radiation Jul 2024The BL17B beamline at the Shanghai Synchrotron Radiation Facility was first designed as a versatile high-throughput protein crystallography beamline and one of five...
The BL17B beamline at the Shanghai Synchrotron Radiation Facility was first designed as a versatile high-throughput protein crystallography beamline and one of five beamlines affiliated to the National Facility for Protein Science in Shanghai. It was officially opened to users in July 2015. As a bending magnet beamline, BL17B has the advantages of high photon flux, brightness, energy resolution and continuous adjustable energy between 5 and 23 keV. The experimental station excels in crystal screening and structure determination, providing cost-effective routine experimental services to numerous users. Given the interdisciplinary and green energy research demands, BL17B beamline has undergone optimization, expanded its range of experimental methods and enhanced sample environments for a more user-friendly testing mode. These methods include single-crystal X-ray diffraction, powder crystal X-ray diffraction, wide-angle X-ray scattering, grazing-incidence wide-angle X-ray scattering (GIWAXS), and fully scattered atom pair distribution function analysis, covering structure detection from crystalline to amorphous states. This paper primarily presents the performance of the BL17B beamline and the application of the GIWAXS methodology at the beamline in the field of perovskite materials.
PubMed: 38917022
DOI: 10.1107/S1600577524004764 -
The Review of Scientific Instruments Jun 2024Depth-selective x-ray diffraction (XRD) technique was developed. In this technique, XRD spectra were measured using an energy dispersive (ED) x-ray detector at fixed...
Depth-selective x-ray diffraction (XRD) technique was developed. In this technique, XRD spectra were measured using an energy dispersive (ED) x-ray detector at fixed angles. A straight capillary optic was used to define the incident x-ray beam, and a second straight capillary defined the beam path from the sample to detector. Thereby, only the XRD spectrum at the small intersection of two capillary optics could be obtained. A depth-selective XRD is possible by changing the sample position in depth. Many XRD peaks appear in a high-energy range more than 10 keV in the ED spectrum. The detection of these peaks will be advantageous for depth analysis because of low absorption in the sample. Depth-selective measurement would be advantageous over general XRD. In this study, depth-selective and ED-XRD spectra are demonstrated for the layered sample, which consisted of film-like Si powder and a muscovite film.
PubMed: 38916452
DOI: 10.1063/5.0191425 -
Nanoscale Jun 2024Fluocerite is a rare earth element (REE) fluoride found as an accessory mineral in magmatic-hydrothermal REE ore deposits, including alkaline complexes and carbonatites,...
Fluocerite is a rare earth element (REE) fluoride found as an accessory mineral in magmatic-hydrothermal REE ore deposits, including alkaline complexes and carbonatites, where it is often associated with REE-fluorocarbonates. This study investigates the crystallisation kinetics, mechanisms and energetics of fluocerite (REEF) and its role as a precursor phase of bastnäsite, one of the key minerals used for the extraction of REE. Fluocerite was synthesized by reacting pure fluorite (CaF) with La-, Ce- and Nd-bearing solutions at temperatures ranging from ambient to low hydrothermal (30-90 °C). The synthetic fluocerites were then placed in contact with NaCO solutions at temperatures up to 200 °C. A combined approach using powder X-ray diffraction and scanning electron microscopy with energy dispersive spectroscopy was used to determine the nature and quantify the crystallising solids. Our findings reveal a temperature-dependent fluorite-fluocerite transformation, with completion observed within 1 hour at 90 °C and extending to around 30 days at 30 °C. The rate of crystallisation decreases proportionally with the atomic number of the rare earth elements. On the other hand, the carbonation reaction of fluocerite exhibits a significantly slower rate, by ∼3 orders of magnitude, in comparison to the fluorite-fluocerite transformation, regardless of temperature conditions. The synthetic La, Ce and Nd fluocerites transformed into bastnäsite at all temperatures, also forming cerianite (CeO) in the Ce-bearing experiments and metastable kozoite, NdCOOH, in the Nd-bearing experiments. Activation energies of fluocerite nucleation increase proportionally with the ionic radii of the REE (81 ± 6 (La); 84 ± 5 (Ce), 96 ± 10 (Nd) kJ mol), while the activation energies associated with fluocerite crystallisation are slightly higher for La (90 ± 12 kJ mol) and similar for Ce and Nd (76 ± 12 and 72 ± 8 kJ mol, respectively).
PubMed: 38916174
DOI: 10.1039/d4nr01614a -
Dalton Transactions (Cambridge, England... Jun 2024This study presents evidence that lead metavanadate, PbVO, is a material with zero-linear compressibility, which maintains its crystal size in one crystallographic...
This study presents evidence that lead metavanadate, PbVO, is a material with zero-linear compressibility, which maintains its crystal size in one crystallographic direction even under external pressures of up to 20 GPa. The orthorhombic polymorph of PbVO (space group ) was studied up to 20 GPa using synchrotron powder X-ray diffraction, Raman spectroscopy, and density-functional theory simulations to investigate its structural and vibrational evolution under compression. Up to this pressure we find no evidence of any structural phase transitions by any diagnostic technique, however, a progressive transformation of the coordination polyhedron of vanadium atoms is revealed which results in the zero-linear compressibility. High-pressure Raman experiments enabled the identification and symmetry assignation of all 54 zone-centre Raman-active modes as well as the calculation of their respective pressure coefficients. Three independent high-pressure powder X-ray diffraction experiments were performed using different pressure-transmitting media (Ne, 4 : 1 methanol-ethanol mixture, and silicone oil). The results show a high anisotropic behaviour in the linear compressibility of the crystallographic axes. The PbVO bulk modulus of 86.1(9) GPa was determined using a third-order Birch-Murnaghan equation of state. The experimental results are supported by density-functional theory calculations, which provide vibrational patterns, unit-cell parameters, and atomic positions. These calculations also reveal that, unlike MgVO and ZnVO, the band gap of PbVO closes with pressure at a rate of -54 meV GPa due to the contribution of the Pb 6s orbital to the top of the valence band.
PubMed: 38916062
DOI: 10.1039/d4dt01321b -
Cureus May 2024Background Graphene is a versatile material with promising applications in various fields such as electronics, energy, biomedicine, and the environment due to its...
Background Graphene is a versatile material with promising applications in various fields such as electronics, energy, biomedicine, and the environment due to its exceptional mechanical strength, thermal and electrical conductivity, transparency, and chemical stability. Graphene has been extensively used in biological and medical settings. MXene is a two-dimensional (2D) material that exhibits a strong affinity for water and electrical conductivity because of its surface terminations (oxygen {-O}, fluorine {-F}, and hydroxyl {-OH}) and transition metal carbide or nitride. MXene has attracted significant attention recently for its wide range of applications and unique properties. This study focuses on the synthesis and characterization of graphene-functionalized MXene. Furthermore, we investigated its cytotoxic effects on cancer cell lines. The characterization of graphene-functionalized MXene is carried out using scanning electron microscopy (SEM), X-ray diffraction(XRD), and Fourier transform infrared spectroscopy (FTIR) assays. Materials and methods Graphene powder was finely ground in isopropyl alcohol and then sonicated for two hours to produce solution A. MXene was synthesized by reacting titanium aluminum carbide (TiAlC) with hydrofluoric acid (HF). A mixture of TiAlC and HF was heated to 40°C with continuous stirring for 24 hours to form solution B. Subsequently, solutions A and B were combined and stirred for 30 minutes. The resulting mixture was transferred to a hydrothermal reactor and maintained at 180°C for 12 hours. After the completion of the reaction, the resulting material was cooled to room temperature and purified through washing with distilled water, ethanol, and acetone. The sample was then dried at 80°C for 12 hours. Results The X-ray diffraction (XRD) study confirms the formation of graphene-functionalized titanium carbide (TiC). The sharp peaks indicate a highly crystalline nature. Graphene is a sheet-like structure with numerous gaps. Particles exhibit a multitude of voids and pores on their surfaces. Upon incorporation, graphene displays a small sheet-like structure. Graphene-functionalized titanium carbide confirms the presence of distinct layered or sheet-like structures stacked together. Following the addition of the material, some cancer cells are eradicated, and they exhibit increased biocompatibility, demonstrating anticancer activity. Conclusion Graphene-functionalized titanium carbide has been successfully synthesized and characterized, as evidenced by various analytical methods such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and methyl-thiazoldiphenyl-tetrazolium (MTT) assays. The cytotoxic impact of the synthesized graphene-functionalized titanium carbide on cancer cell lines was examined. The findings reveal a notable cytotoxic effect, indicating its potential as an anticancer agent. Further research in collaboration with experts from diverse fields will be crucial to advance and translate this technology into practical applications for cancer patients. Future scope Graphene and titanium carbide are promising materials for cancer research, biomedical applications, and imaging. Nevertheless, additional research is required to comprehend their mechanisms, enhance their properties, assess their safety and efficacy, and conduct clinical trials.
PubMed: 38915990
DOI: 10.7759/cureus.61049 -
Drug Delivery and Translational Research Jun 2024(20 S)-Ginsenoside Rh2 is a natural saponin derived from Panax ginseng Meyer (P. ginseng), which showed significantly potent anticancer properties. However, its low...
(20 S)-Ginsenoside Rh2 is a natural saponin derived from Panax ginseng Meyer (P. ginseng), which showed significantly potent anticancer properties. However, its low water solubility and bioavailability strongly restrict its pharmaceutical applications. The aim of current research is to develop a modified (20 S)-Ginsenoside Rh2 formulation with high solubility, dissolution rate and bioavailability by combined computational and experimental methodology. The "PharmSD" model was employed to predict the optimal polymer for (20 S)-Ginsenoside Rh2 solid dispersion formulations. The solubility of (20 S)-Ginsenoside Rh2 in various polymers was assessed, and the optimal ternary solid dispersion was evaluated across different dissolution mediums. Characterization techniques included the Powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FTIR). Molecular dynamics simulations were employed to elucidate the formation mechanism of the solid dispersion and the interactions among active pharmaceutical ingredient (API) and excipient molecules. Cell and animal experiments were conducted to evaluate the in vivo performance of the modified formulation. The "PharmSD" solid dispersion model identified Gelucire 44/14 as the most effective polymer for enhancing the dissolution rate of Rh2. Subsequent experiment also confirmed that Gelucire 44/14 outperformed the other selected polymers. Moreover, the addition of the third component, sodium dodecyl sulfate (SDS), in the ternary solid dispersion formulation significantly amplified dissolution rates than the binary systems. Characterization experiments revealed that the API existed in an amorphous state and interacted via hydrogen bonding with SDS and Gelucire. Moreover, molecular modeling results provided additional evidence of hydrogen bonding interactions between the API and excipient molecules within the optimal ternary solid dispersion. Cell experiments demonstrated efflux ratio (EfR) of Rh2 ternary solid dispersion was lower than that of pure Rh2. In vivo experiments revealed that the modified formulation substantially improved the absorption of Rh2 in rats. Our research successfully developed an optimal ternary solid dispersion for Rh2 with high solubility, dissolution rate and bioavailability by integrated computational and experimental tools. The combination of Artificial Intelligence (AI) technology and molecular dynamics simulation is a wise way to support the future formulation development.
PubMed: 38914874
DOI: 10.1007/s13346-024-01628-4 -
ACS Omega Jun 2024A three-dimensional heterobimetallic porous structure with the formula {[YTbL(OH)(HO) (DMF)] ·1.5HO·DMF} (L = 3-amino-4-hydroxybenzoate) () has been synthesized and...
A three-dimensional heterobimetallic porous structure with the formula {[YTbL(OH)(HO) (DMF)] ·1.5HO·DMF} (L = 3-amino-4-hydroxybenzoate) () has been synthesized and characterized by single crystal and powder X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), inductively coupled plasma mass spectrometry (ICP-MS), electrophoretic mobility, and Fourier transform infrared (FTIR) spectroscopy. The structure presents two metal environments: a bioaugmented isosceles wedge (mm2) MO and a tricapped trigonal prism (-6m2) MNO. These configurations facilitate the creation of channels with a diameter of 10.7 Å, enabling its utilization as an active catalyst where the heterobimetallic nature of the assembly will be explored. This mixed-metal metal-organic framework has been tested in the cycloaddition of epoxides with carbon dioxide as well as in the cyanosilylation and hydroboration reactions of carbonylic substrates. Additionally, a monometallic analogue has been synthesized for comparative evaluation of their catalytic performances. Both the mixed metal and monometallic variants exhibit outstanding activity in the cyanosilylation and hydroboration of carbonyls and in the synthesis of carbonates under CO pressure. However, only the latter exhibits high recyclability.
PubMed: 38911723
DOI: 10.1021/acsomega.4c03109 -
Spectrochimica Acta. Part A, Molecular... Jun 2024The synthesis of carbon quantum dots (CQDs) using chemical precursors with different organic groups is a strategy to improve optical properties and expand applications...
The synthesis of carbon quantum dots (CQDs) using chemical precursors with different organic groups is a strategy to improve optical properties and expand applications in several fields of research such as Analytical Chemistry. Ascorbic acid and riboflavin are widely used in human food supplementation, making quality monitoring of these vitamin supplements relevant and necessary. In this work, disodium ethylenediaminetetraacetic, sodium thiosulfate and urea were applied to obtain CQDs through a single-step microwave-assisted synthesis. The CQDs were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction, infrared spectroscopy, zeta potential measurements, ultraviolet-visible spectroscopy and photoluminescence spectroscopy. The synthesized nanoparticles exhibited satisfactory and stable optical properties with luminescence at 430 nm, water solubility, and fluorescence quantum yield of 8.9 %. They were applied in the quantification of ascorbic acid and riboflavin in vitamin supplements. The fluorescence mechanisms observed were dynamic quenching for the CQDs/Cr(VI) sensor, followed by a return of fluorescence in the presence of ascorbic acid, and static quenching and inner filter effect in the interaction with riboflavin. Factorial designs 2 and 2 were used to optimize the analytical parameters. The CQDs/Cr(VI) sensor used in the determination of ascorbic acid, employing an on-off-on strategy, resulted in a linear range of 0.5 to 50 µg mL and a limit of detection of 0.15 µg mL. The ratiometric fluorescence used in the determination of riboflavin resulted in a linear range of 0.1 to 7 µg mL and a limit of detection of 0.09 µg mL. The analytical results for ascorbic acid were compared to the reference method of the Brazilian pharmacopeia, showing accuracy and precision according to the Brazilian Health Regulation Agency. Therefore, the synthesized CQDs were used to determine ascorbic acid and riboflavin in vitamin supplements, and the application of this nanomaterial can be expanded to different analytes and matrices, using simple and low-cost analysis techniques.
PubMed: 38909560
DOI: 10.1016/j.saa.2024.124669 -
Inorganic Chemistry Jun 2024A remarkable increase in the luminescent intensity of Er-doped CaF up-conversion phosphors was achieved, showing an approximate enhancement of over 1100-fold. This...
A remarkable increase in the luminescent intensity of Er-doped CaF up-conversion phosphors was achieved, showing an approximate enhancement of over 1100-fold. This enhancement was realized by incorporating Yb, Al, Sr, and gold nanospheres and nanorods. The substantial improvement in up-converting luminescence effectively enhances sensitivity and efficiency at low excitation power densities. The up-conversion phosphors, consisting of (Ca,Sr)F:Er,Yb,Al, were easily prepared using excess NHF flux at 950 °C for 30 min. The structural confirmation of interstitial Al ions within the CaF lattice was achieved through synchrotron powder X-ray powder diffraction. The significant enhancement of up-conversion emission and their mechanisms in the phosphors were vividly represented through energy transfer, interstitials and local distortions, and localized surface plasmon resonances when excited with a 980 nm diode laser.
PubMed: 38906836
DOI: 10.1021/acs.inorgchem.4c01814