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Artemisinin (ART) is a most promising antimalarial agent. However, its low aqueous solubility limits its oral absorption, resulting in low bioavailability. In this study, we have successfully discovered a novel cocrystal with 2-methyl resorcinol (ART-2MRE) providing improved solubility compared with a previously reported cocrystal with resorcinol (ART-RES). Single crystal X-ray structure analysis revealed that the ART-2MRE cocrystal was composed of ART and 2MRE in a molar ratio of 2 : 1. Though the ART-2MRE and ART-RES cocrystals were found to have similarities in their crystal structures, with one layer of a cocrystal former and two layers of ART arranged in alternating rows, the ART-2MRE cocrystal showed higher dissolution rate than ART-RES cocrystal. In situ real-time low-frequency (LF) Raman monitoring and powder X-ray diffraction (PXRD) measurements of the crystals during the dissolution test proved useful to investigate the dissolution behavior of the cocrystals. Low-frequency Raman monitoring revealed that as dissolution progressed, there was a continuous shift from the peak unique to the ART-2MRE cocrystal to the peak unique to the ART stable form. Similar observations were obtained in PXRD measurements as well. Furthermore, experiments were conducted by adding a polymer to the dissolution test solution to investigate the dissolution behavior under supersaturation, indicating the possibility of differences in the dissolution behavior between the ART-2MRE cocrystal and ART-RES cocrystal. Understanding the dissolution behavior from cocrystals is essential in developing cocrystals. [ABSTRACT FROM AUTHOR]

Soluble aluminum alloy materials used in underground operational tools are synthesized via a high-temperature smelting process. The microstructure and composition distribution of the alloy were analyzed using X-ray diffraction, metallographic microscopy, and scanning electron microscopy with energy-dispersive X-ray and electron backscatter diffraction techniques. The mechanical properties were evaluated using a universal testing machine and hardness tester, while solubility assessments were conducted in a constant-temperature water bath. This study focuses on the plasticity and dissolution characteristics of Al-Mg-Ga-Sn-In alloys with varying Mg contents. The tensile strength (σb) of the alloy was 181.99 MPa, with an elongation (δ) of 27.49% and cross-sectional shrinkage (φ) of 11.67% at a magnesium content of 3.0 wt.%. Additionally, in the compressive test, the compressive yield strength (σsc) was recorded at 188.32 MPa, while the compression rate (δ) was 27.06% and the section expansion rate (φ) was 138.66%. Furthermore, the alloy demonstrated the ability to dissolve spontaneously in water at 90 °C, exhibiting an average dissolution rate of 1.0 g·h−1cm−2 and a maximum dissolution rate of 3.25 g·h−1cm−2 after 12.0 h. Consequently, this alloy composition not only satisfies the requirements for rapid solubility but also exhibits favorable plasticity, providing a novel reference for the selection of soluble aluminum alloy materials. [ABSTRACT FROM AUTHOR]

This paper investigates the dissolution of two biopolymers, cellulose and silk fibroin, in a mixture of 1-ethyl-3-methylimidazolium acetate (EmimAc) and dimethyl sulphoxide (DMSO). EmimAc is a promising environmentally friendly solvent currently in wide use but can be limited by its high viscosity, which inhibits the speed of dissolution. To mediate this, DMSO has been used as a cosolvent and has been shown to significantly lower the solution viscosity and aid mass transport. Dissolution experiments are carried out separately for both cellulose and silk fibrion with a range of EmimAc:DMSO ratios from 100 wt% EmimAc to 100 wt% DMSO. Interestingly, the optimal EmimAc:DMSO ratio (in terms of dissolution speed) is found to be very different for the two biopolymers. For cellulose, a mixture of 20 wt% EmimAc with 80 wt% DMSO is found to have the fastest dissolution speed, while for silk fibroin, a ratio of 80 wt% EmimAc with 20 wt% DMSO proves the fastest. These dissolution trials are complemented by rheological and nuclear magnetic resonance experiments to provide further insight into the underlying mechanisms. Finally, we produce hybrid biopolymer films from a solution to show how this work provides a foundation for future effective dissolution and the preparation of hybrid biopolymer films and hybrid biocomposites. [ABSTRACT FROM AUTHOR]

This study explores for the first time the impact of chitosan (CS) with varying molecular weights (MW), orange peel extract concentration, and hydroxypropyl methylcellulose (HPMC) content on the formulation of buccal tablets for treating oral infections. Utilizing a statistical design of experiments (DoE), nine different formulations were evaluated for mechanical properties, dissolution behavior, mucoadhesion, and biological activity. A formulation with high CS MW, 60% orange peel extract, and 8% HPMC, emerged as the optimal formulation, demonstrating superior tabletability, compressibility, and compactibility. Dissolution studies indicated that hesperidin release followed the Higuchi model, with higher extract content enhancing this phenomenon. Mucoadhesion improved with increased HPMC and CS concentrations, although higher extract content reduced bioadhesion. Biological assays showed that higher extract levels boosted antioxidant activity, while CS primarily contributed to anti-inflammatory effects. The optimized formulation exhibited broad antimicrobial activity against key oral pathogens, surpassing the effectiveness of the individual components. Principal component analysis (PCA) further confirmed the significant influence of extract content on tablet properties. These findings suggest that the optimized tablet formulation holds promise for effective buccal delivery in the treatment of oral infections, warranting further investigation in clinical settings. [ABSTRACT FROM AUTHOR]

The present monograph discusses the possibility of BCS-based biowaivers for immediate release pharmaceutical products containing raltegravir potassium, which is used to treat human immunodeficiency virus (HIV) infections. Raltegravir potassium can be assigned to BCS class II or IV since this compound has low solubility and uncertain permeability. Therefore, according to the ICH M9 guideline, it is not recommended to apply BCS-based biowaiver to approval of immediate release solid dosage forms of raltegravir potassium, either for new generic versions or when moderate to major changes in composition and/or the manufacturing method of the product are made. [ABSTRACT FROM AUTHOR]

The European Commission (EC) has tasked the European Medicines Agency (EMA) to provide a recommendation towards the acceptability of titanium dioxide (TiO 2) in pharmaceutical products by early 2024 to inform on final decision in early 2025[1]. Unlike the already implemented ban of TiO 2 in foods, removing this excipient from pharmaceutical products will likely have significant impact on the pharmaceutical industry, regulatory agencies, and patients. This commentary explores the challenges facing the pharmaceutical industry tasked with supporting the development and registration of TiO 2 free (TF) drug products. Specifically, justification of formulation changes and potential impact to in vitro and in vivo performance, as well as differences in global regulatory comparative dissolution requirements to justify changing to TF drug product are discussed. Particularly, the uncertainties around how a formulation change such as removal of TiO 2 from immediate release solid oral dosage forms will be viewed in Europe compared to other regions is discussed. To respond to these challenges and avoid disruption to the medicines supply chain in case in vitro data such as dissolution is either too challenging or insufficient to justify changing to TF product, pharmaceutical companies may have to decide if the level of risk is worth the effort needed to reformulate, develop, and register a new TF product. [ABSTRACT FROM AUTHOR]

This study aims to clarify the process of oral drug absorption from jelly formulations. Agar and pectin-based jellies containing drugs with different membrane permeability (high: antipyrine [ANT], medium: metoprolol [MET], low: atenolol [ATE]) were prepared and tested for in vitro drug release and in vivo drug absorption in rats. All drugs showed similar release profiles in vitro from both jelly formulations, except for the faster release from pectin jelly at neutral pH. In contrast, in vivo absorption of ATE but not of ANT from jelly formulations was significantly lower than from solution. Absorption of ATE and MET was low from agar jelly after oral administration, whereas additional water intake significantly increased the absorption. The process of drug absorption was described by the compartmental model consisting of jelly, intestinal fluid, and blood compartments. Drugs in the jelly diffuse into the intestinal fluid and then permeate the intestinal membrane. By considering the rate-limiting process, membrane permeability-dependent drug absorption from agar jelly and the effects of water intake were identified. In conclusion, jelly formulations may potentially decrease and delay drug oral absorption, especially of poorly permeable drugs. Intestinal fluid volume is one of the important factors to control the drug absorption. [Display omitted] • Although oral jelly formulations are often used for pediatric or elderly patients because of their high swallowability, the precise process and mechanism of gastrointestinal (GI) drug absorption from oral jelly formulations are not fully understood. This study examined the process of drug absorption from oral jelly formulations. • In this study, the compartmental model was used to describe the unique process of drug absorption from oral jelly formulations, in which drugs dissolved in the jelly reach the intestinal fluid via diffusion through the jelly matrix. By defining the rate-limiting process of drug absorption from oral jelly formulations, the effects of the membrane permeability of the drug and GI fluid volume were identified. • The correlation between in vitro drug release and in vivo oral absorption from oral jelly formulations observed in this study will help to consider the bioequivalence of oral jelly formulations with other formulations (e.g., solution, tablet). • To clearly demonstrate the effect of membrane permeability, three model drugs with different permeabilities were incorporated in the jelly and administered to rats as a cassette. • Two different methods, intra-intestinal and oral administration, were used for in vivo drug administration to rats. The results of the intra-intestinal administration study revealed the basic mechanism of drug absorption from oral jelly formulations, whereas the oral administration study highlighted the clinical importance of water intake for drug absorption. [ABSTRACT FROM AUTHOR]

In the previous decade, organic aqua regia (OAR) was discovered as a mixture of pyridine and thionyl chloride that has been observed to surprisingly yet notably selectively dissolve precious metals, dissolution‐resistant gold. Given the novel combination is two common organic solvents, it has immense potential to contribute to a circular economy of metal recycling, economically and environmentally. The underlying mechanisms behind its metal dissolution and interesting properties are not well‐understood. Using both the original mixture and derivatives, the role of each OAR reagent was analyzed in the dissolution of gold to begin probing and illuminating the novel mechanism. Three mechanisms were proposed: radical based, oxidant and ligand, and Lewis acid and base. Computational means were used to propose possible mechanisms. Experiments were used to explicate the possible mechanisms. Discoveries from the original publication were used to verify assessments and suggest future areas of study for further confirmation. Based on the finding that 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO) does not significantly affect the amount of gold dissolved, the radical mechanism was dismissed. Findings from experiments replacing pyridine with its derivatives disproved the likelihood of the oxidant and ligand mechanism. Finally, with the support of proton nuclear magnetic resonance (1H NMR) and other characterization techniques, the Lewis acid and base mechanism was determined to be the most probable mechanism of OAR. The mechanistic findings reported herein will pave the way for continued understanding of the mechanism to be exploited and optimized for other metals and organometallic chemistry in the recycling of metals. [ABSTRACT FROM AUTHOR]

One major factor impeding the design of nuclear waste glasses with enhanced waste loadings is our insufficient understanding of their composition–structure–durability relationships, specifically in the environments the waste form is expected to encounter in a geological repository. In particular, the high field‐strength cations (HFSCs) are an integral component of most waste streams. However, their impact on the long‐term performance of the glassy waste form remains mostly undeciphered. In this context, the present study aims to understand the impact of some HFSCs (i.e., Nb5+, Zr4+, Ti4+, and La3+) on the dissolution behavior of alkali/alkaline‐earth aluminoborosilicate‐based model nuclear waste glasses in hyper‐alkaline media. At pH = 13, the studied glasses dissolve through the dissolution–reprecipitation mechanism, with Ca precipitation being the most vital step to passivation. In Ca‐free glasses, although the HFSCs slow down the forward rate, they do not seem to impact the residual rate behavior of glasses. The presence of Ca2+, however, initiates the rapid precipitation of network polymerizing HFSCs (i.e., Nb5+, Zr4+, and Ti4+) into a Ca2+/HFSCs‐based passivating layer, thus suggesting a synergy between Ca2+ and HFSCs that contributes to the enhanced long‐term durability of the glasses. Such synergy is not strongly evident for La3+, but instead, a potential La/Si affinity is observed upon the formation of the alteration layer. [ABSTRACT FROM AUTHOR]

Calcium nitrate (CN: Ca(NO3)2) has been shown to mitigate alkali–silica reaction (ASR) in concrete. Such ASR mitigation has been suggested to be on account of precipitate (i.e., barrier or passivation layer) formation‐induced dissolution inhibition of reactive/dissolving aggregate surfaces. Herein, we examine the ability of CN to mitigate ASR across two cements (Type I/II and Portland Limestone Cement), for aggregates of varying reactivity, and across different types and dosages of SCMs (supplementary cementitious materials, i.e., amorphous steel slag and Class C and Class F fly ashes). Based on expansion measurements carried out as per ASTM C1260/C1567, it is observed that CN, as a function of dosage, substantively mitigates ASR in mortar formulations across aggregate types. Careful microstructural examinations, dissolution studies, and thermodynamic calculations indicate that CN induces the formation of C–S–H, portlandite (Ca(OH)2), and calcite (CaCO3) precipitate mixtures, which form on aggregate surfaces at the expense of typical ASR gels. Such precipitates create a dissolution barrier and inhibit ASR in both SCM‐free and SCM‐containing formulations. The outcomes indicate that CN is an efficient and cost‐effective ASR mitigation additive (∼$250–$600 per tonne), particularly in a time of dwindling fly ash supplies and unaffordable lithium prices (>∼$12 000 per tonne). [ABSTRACT FROM AUTHOR]

Designing waste forms using the cocktail effect of high‐entropy ceramics can improve the efficiency of ceramic waste forms. In this work, traditional garnet (Y1.2Nd1.8Fe5O12, YIG) and high‐entropy (HE) garnet (Y0.6Gd0.6Sm0.6Eu0.6Dy0.6Fe5O12, HEG) are synthesized through ignition and plasma sintering to form dense ceramic waste forms. The chemical stability of YIG and HEG was studied by using static leaching tests at pH = 3, 5, 7, 9, 11. The results indicate that acidic environments can increase the leaching rate of ceramics. Leaching behavior leads to a decrease in lattice volume, but the elements remain uniformly distributed. The leaching mechanism indicates that YIG and HEG are controlled by dissolution and surface effect in the early stage (1–7 days) of leaching. The leaching mechanism in the later stage (14–42 days) is characterized by diffusion control. The diffusion coefficient of long‐term leaching indicates that HEG is more suitable as the immobilization substrate for high‐level radioactive waste (HLW) than YIG. [ABSTRACT FROM AUTHOR]

Soil caves collapse are typical geological hazards in karst areas. The disintegration of red clay is one of the important mechanisms leading to soil caves collapse. The pH of the soil pore solution has changed due to acid rains and the overuse of fertilizers. This study conducted disintegration tests to observe the disintegration rate of red clay in solutions with different pH values by a self-made disintegration apparatus. The inductively coupled plasma mass spectrometer (ICP-MS) and Zeta potential analyzer were used to test the cations concentration in the solutions and the electric potential (ζ potential) of red clay, analyzing the effect of pH on the physicochemical properties and the disintegration rate of red clay, providing a scientific basis for evaluating and preventing soil caves collapse. The results show that the disintegration rate in solutions with different pH values follows the order of pH = 11 > pH = 9 > pH = 3 > pH = 5 > pH = 7. When pH < 7, the cations concentration and the cations charges density in the soil solutions increased as the pH decreases. The electric potential changed from negative to positive as the pH decreases, with the potential value first decreasing and then increasing. When pH > 7, the cations concentration, cations charges density in the soil solutions, and the electric potential increased with the pH increased. The ratio of charges density to electric potential increased under both acidic and alkaline conditions, the thickness of the clay diffusion layer decreased, short-range gravitational decayed and repulsion increased, ultimately leading to the disintegration of red clay. [ABSTRACT FROM AUTHOR]

Green rusts (GR) are mixed-valence iron (Fe) hydroxides which form in reducing redox environments like riparian and wetland soils and shallow groundwater. In these environments, silicon (Si) can influence Fe oxides' chemical and physical properties but its role in GR formation and subsequent oxidative transformation have not been studied starting at initial nucleation. Green rust sulfate [GR(SO4)] and green rust carbonate [GR(CO3)] were both coprecipitated from salts by base titration in increasing % mol Si (0, 1, 10, and 50). The minerals were characterized before and after rapid (24 h) aqueous air-oxidation by x-ray diffraction (XRD), scanning electron microscopy (SEM), Fe extended x-ray absorption fine structure spectroscopy (EXAFS), and N2-BET surface area. Results showed that only GR(SO4) or GR(CO3) was formed at every tested Si concentration. Increasing % mol Si caused decreased plate size and increased surface area in GR(CO3) but not GR(SO4). GR plate basal thickness was not changed at any condition indicating a lack of Si interlayering. Air oxidation of GR(SO4) at all % mol Si contents transformed by dissolution and reprecipitation into lepidocrocite and goethite, favoring ferrihydrite with higher % Si content. Air oxidation of GR(CO3) transformed into magnetite and goethite but increasing Si caused GR to oxidize while retaining its hexagonal plate structure via solid-state oxidation. Our results indicate that Si has the potential to cause GR to form in smaller particles and upon air oxidation, Si can either stabilize the plate structure or alter transformation to ferrihydrite. [ABSTRACT FROM AUTHOR]

The diverse range of patterns in porous media formed by dissolution processes depends on the relative magnitude of flow, transport, and chemical reactions at pore surfaces. However, distinguishing between regimes often relies solely on qualitative, visual comparisons of emergent structures. Here, we propose a quantitative measure capable of identifying different regimes using the concept of the spatial flow focusing profile, which segments the medium into cross sections along the flow direction to calculate the flow focusing index for each section. We employ this measure in numerical simulations of a dissolving porous medium using a pore network model. We obtain a morphological phase diagram of dissolution patterns, which we characterize using the flow focusing profile. In particular, we demonstrate that analyzing the temporal changes in the profile allows one to quantitatively distinguish between wormholing and channeling. The transition between them is shown to be affected by the heterogeneity of the system. Plain Language Summary: When rock dissolves, it creates different patterns depending on the interplay of flow, reactant transport, and chemical kinetics. These patterns are classified into various types, known as dissolution regimes. However, this classification is often based solely on visual examination of the final structures and lacks quantitative criteria. In this study, we propose a tool that considers cross sections of the material and measures the focusing of flow in each slice. For example, flow can be uniform across most of the cross section or focused in a small number of channels. Based on how this flow focusing changes in space and time, we assign the patterns to dissolution regimes. Using this tool, we demonstrate that accurately describing the patterns resulting from dissolution requires knowledge of their evolution history. Predicting dissolution regimes for a given flow rate, reaction rate, and pore geometry is essential in practical applications, such as geological carbon sequestration or nuclear waste storage, where the emergence of highly conductive dissolution channels must be prevented at all costs. Key Points: Dissolution regimes can be quantitatively distinguished using the concept of the flow focusing profileTemporal changes of the flow focusing profile differentiate the wormholing and channeling regimesPore structure heterogeneity shifts the transition between dissolution regimes [ABSTRACT FROM AUTHOR]

Geochemical investigation of hydrogen (H 2), brine, rock formations, and residual gases (nitrogen – N 2 , methane – CH 4 , and carbon dioxide – CO 2) is crucial for understanding H 2 storage processes in depleted gas reservoirs. This study examines the effects of injecting a gas mixture (60% H 2 + 30% N 2 + 5% CH 4 + 5% CO 2) into Bandera Grey sandstone with notable clay mineral content. The experiment lasted 50 days at 42 °C, 1350 psi, and 5 wt% NaCl brine, with detailed analytical characterization before and after aging. Results show minimal sample reactivity, causing slight alterations in petrophysical characteristics. Dissolution primarily affected dolomite and barite minerals, while illite and kaolinite caused pore blockage. Gas chromatography data indicate only 0.45% of injected H 2 is lost (via dissolution in brine and reaction with CO 2), CH 4 increased by 6.22%, N 2 remained stable, and CO 2 decreased by 1%. These results provide valuable insights into the feasibility and safety of utilizing depleted gas reservoirs for H 2 storage. • Effect of storing 60% H 2 and 40% cushion gas in clay-rich sandstone is investigated. • Geochemical reactions (dissolution/precipitation) induced by the mixture are very weak. • PH increased from 6.13 to 7.24 led to mineral dissolution and precipitation. • Only 0.45% of injected H 2 was lost based on gas chromatography. • Findings provide insights into the feasibility and safety of depleted gas reservoirs for H 2 storage. [ABSTRACT FROM AUTHOR]

The alloying elements in 8Cr4Mo4V bearing steel tend to form large primary carbides with carbon, which not only causes element segregation but also becomes the primary source of fatigue crack initiation, thereby decreasing the material's usability and machinability. Owing to the excellent thermal stability of primary carbides, traditional homogenization annealing requires high temperatures, which is both time‐ and energy‐intensive. Excessively high heat treatment temperatures can also result in “overburning” of the sample. Herein, primary carbides are rapidly dissolved at low temperatures using pulsed electric current treatment. The additional free energy introduced by the pulsed electric current lowers the thermodynamic barrier for carbide dissolution. During the second‐phase dissolution process, the unbalanced diffusion of elements may cause the formation of Kirkendall voids. Due to the difference in electrical conductivity between the voids and the matrix, the pulsed electric current generates thermal compressive stress on the voids, promoting rapid atom migration to these voids and accelerating their healing. This pulse‐current treatment technology offers a novel method for the rapid dissolution of carbides in alloys at low temperatures and for the rapid healing of related voids. [ABSTRACT FROM AUTHOR]

Prussian blue analogs (PBAs) are promising insertion‐type cathode materials for different types of aqueous batteries, capable of accommodating metal or non‐metal ions. However, their practical application is hindered by their susceptibility to dissolution, which leads to a shortened lifespan. Herein, we have revealed that the dissolution of PBAs primarily originates from the locally elevated pH of electrolytes, which is caused by the proton co‐insertion during discharge. To address this issue, the water‐locking strategy has been implemented, which interrupts the generation and Grotthuss diffusion of protons by breaking the well‐connected hydrogen bonding network in aqueous electrolytes. As a result, the hybrid electrolyte enables the iron hexacyanoferrate to endure over 1000 cycles at a 1 C rate and supports a high‐voltage pH‐decoupled cell with an average voltage of 1.95 V. These findings provide insights for mitigating the dissolution of electrode materials, thereby enhancing the viability and performance of aqueous batteries. [ABSTRACT FROM AUTHOR]

The geopolymerization reaction is a chemical process involving the dissolution of amorphous, semi-crystalline and crystalline phases following alkaline or acid attack at ambient or at low temperature (T˂100 °C). Together with precondensed entities of the used activator solution the dissolved parts form a geopolymer network which glues together all remaining unreacted parts as ingredients of the artificial stone. The fate of the mineralogical phases present in the precursors used in the synthesis of alkaline and acid geopolymers is reviewed in this article. The different starting materials used in the synthesis of geopolymers and the different techniques used to modify the reactivity of these materials are reported. The mineralogical evolution of the amorphous, semi-crystalline and crystalline phases after activation at ambient and at low temperatures (T < 100 °C) is also reported. This study shows that for the mineralogical investigation of raw material, precursors and geopolymers, XRD is the most widely used analytical method. The most commonly used method to confirm the participation of crystalline phases in geopolymerization is the comparison of the diffractograms of the raw material to those of the products. It also indicates that, in addition to the amorphous aluminosilicate phases, certain semi-crystalline, and crystalline phases participate in this geopolymerization dynamic either by undergoing total or partial dissolution to form an inorganic macromolecule with an amorphous structure of the zeolitic type and other new minerals. The composition of the phases formed depends on the base material. Increasing the synthesis temperature promotes the dissolution of phases, the formation of geopolymer networks, and in some cases, the formation of new phases such as sodalities, zeolite A and zeolite P. Little work has been done to quantify the mineralogical phases before and after precursor activation, making it impossible to assess dissolution, the degree of geopolymerization, and mineral formation. The exact structure of the phases formed is often questionable, as most of the papers do not mention their reference structure number. There is also a lack of quantification of the amorphous phase resulting from the hardening of the activating solution and the evaluation of the fraction of the amorphous phase contained in the precursor remains unreacted. The mineralogical investigation must also extend to the quantification of phases using Rietveld refinement with internal standards to correlate these with the physical and mechanical properties of geopolymer products. Additional mineralogical study techniques, such as thin sections, should be used in future work for in-depth mineralogical investigation of geopolymers. [ABSTRACT FROM AUTHOR]

Levocetirizine dihydrochloride is an effective antiallergenic drug applied mostly orally; however, developing a topical formulation for localized treatment could be beneficial. To achieve this, a modified formulation technique is necessary to enhance bioavailability efficiency and minimize possible side effects. Therefore, levocetirizine particles were prepared by immobilization on mesoporous silica material. Both the dihydrochloride form and its free base of levocetirizine were fixed on a silica-type Syloid support. Immobilization of the active ingredient levocetirizine in a free base form on a Syloid support by mixing in a dichloromethane solution provides better surface coverage (65.5%) than immobilization in the dihydrochloride form in water or methanol (24.5% for both). The successful binding of levocetirizine was confirmed by X-ray photoelectron spectroscopy and infrared measurements. The active ingredient in the form of hydrochloride is more likely to be in the pores, while the free base is bound to the surface in larger quantities. The time-dependent levocetirizine release showed that the liberation of the active ingredient from the Syloid is slower than the dissolution of the starting active ingredient itself, so it may be suitable for exerting a more reliable and prolonged local effect. A gel containing a Syloid-fixed levocetirizine free base was tested in vivo in a croton oil-induced ear edema mouse model. When compared to a reference gel, the half-dose formulation containing levocetirizine free base demonstrated a similar efficacy to Fenistil gel, indicating that the new formulation may offer superior effectiveness at lower doses. [ABSTRACT FROM AUTHOR]

An atomic‐scale understanding of how electrocatalyst surfaces reconstruct and transform during electrocatalytic reactions is essential for optimizing their activity and longevity. This is particularly important for the oxygen evolution reaction (OER), where dynamic and substantial structural and compositional changes occur during the reaction. Herein, a multimodal method is developed by combining X‐ray fine structure absorption and photoemission spectroscopy, transmission electron microscopy, and atom probe tomography with electrochemical measurements to interrogate the temporal evolution of oxidation states, atom coordination, structure, and composition on Co2MnO4 and CoMn2O4 cubic spinel nanoparticle surfaces upon OER cycling in alkaline media. Co2MnO4 is activated at the onset of OER due to the formation of ≈2 nm Co‐Mn oxyhydroxides with an optimal Co/Mn ratio of ≈3. As OER proceeds, Mn dissolution and redeposition occur for the CoMn oxyhydroxides, extending the OER stability of Co2MnO4. Such dynamic dissolution and redeposition are also observed for CoMn2O4, leading to the formation of less OER‐active Mn‐rich oxides on the nanoparticle surfaces. This study provides mechanistic insights into how dynamic surface reconstruction and transformation affect the activity and stability of mixed CoMn cubic spinels toward OER. [ABSTRACT FROM AUTHOR]

The obsidian dating method converts the quantity of diffused molecular water within a near‐surface hydration layer to elapsed time using an experimentally derived diffusion coefficient predicted from the structural water content of the glass. Infrared spectroscopic transmission measurements on transparent archaeological samples record vibrational responses of water bands in the near‐infrared region, permitting determination of structural water content (OH), and the amount of diffused ambient water (H2O). In this application, the H2O water band at 5200 cm−1 is measured directly. The accuracy of the approach is assessed by an evaluation of the precision of each contributing variable. The new protocol is evaluated using obsidian artifacts from radiocarbon‐dated deposits at Salamanca Cave in Argentina. [ABSTRACT FROM AUTHOR]

Regarding potential high temperature applications of materials based on the ternary Al2O3-YAG-ZrO2 (AYZ) eutectic system for turbine blades, their environmental behaviour has to be evaluated in near-service conditions. CMAS attack is one of the phenomena limiting lifetime of ceramic E/TBC coatings for aircraft engines. The present study reports an assessment of the reactivity of AYZ eutectic material facing with two molten CMAS. The effect of test duration (up to 500 h), CMAS composition (with or without Fe2O3), microstructure (interlamellar distance), temperature (1250 and 1350 °C) as well as thermal cycling resistance were investigated. Results evidenced that the interaction of CMAS with AYZ eutectic ceramic was limited regardless of the microstructure. No infiltration of molten CMAS within the eutectic ceramic nor mechanical rupture between CMAS and AYZ was observed. The dissolution of AYZ leads to the rapid formation of anorthite with the CMAS components that hinders further reactions. The inward growth of MgAl2O4 spinel in place of the Al2O3 network occurs in accordance with the thermodynamic available data and without any effect on AYZ integrity. [ABSTRACT FROM AUTHOR]

Background: Sacubitril/valsartan, marketed as Azmarda (manufactured by the innovator company) is a cocrystal consisting 6 sacubitril and valsartan molecules, along with sodium cations and water molecules. This formulation is considered a major mechanism of benefit of this molecule. This study was aimed to assess various brands of sacubitril/valsartan in the market for the presence of the cocrystal forms and compare them with Azmarda. a brand of sacubitril/valsartan manufactured by the innovator company. Methods: The study involved analysis of various marketed products containing sacubitril/valsartan tablets, including Azmarda. Both the Azmarda and marketed products were characterized using differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD). Sodium content and dissolution studies were also performed . Results: A total of 16 brands of marketed products including Azmarda were studied. During DSC studies, unique melting pattern was observed in Azmarda, with exothermic peaks of sacubitril/valsartan detected at 140°C and 102°C, respectively. PXRD analysis revealed that none of the products exhibited the same crystal lattice as Azmarda. Azmarda, with a sodium level of 1.773%, was comparable to brand 2 (1.61%), brand 4 (1.73%), and brand 7 (1.58%). Azmarda demonstrated 64% release of sacubitril and 57% release of valsartan within 30 minutes in 0.1N HCl. Brand 7, brand 12, and brand 13 showed 52%, 57%, and 52% release of sacubitril, respectively, and 45%, 52%, and 48% release of valsartan, respectively, in 30 minutes. Conclusion: The absence of identical crystal lattice structures, highlights absence of cocrystalsin generic formulations. Such variations may impact the bioavailability and efficacy, emphasizing the importance of ensuring consistent and reliable therapeutic outcomes. [ABSTRACT FROM AUTHOR]

Quantitative analyses of the species composition and abundance of benthic foraminifers in surface sediments along a submeridional profile in the northeastern East Siberian Sea have revealed three assemblages associated with the middle–outer shelf and upper and middle continental slope. The maximum abundance of "living" benthic foraminifers is found near the shelf break, which is possibly related to enhanced sea surface bioproductivity. Active dissolution of calcareous microfossils has been detected in the shelf area whereas preservation of calcareous tests becomes better with depth. Some micropaleontological and grain-size data indirectly point to the development of compensatory currents on the middle–outer shelf in the East Siberian Sea. [ABSTRACT FROM AUTHOR]

The Václav vein (Březové Hory deposit, Příbram ore area, Czech Republic) is a base–metal vein containing minor Cu-Zn-Pb-Ag-Sb sulfidic mineralization in a usually hematitized gangue. A detailed mineralogical study using an electron microprobe revealed a complicated multistage evolution of the vein. Early siderite and Fe-rich dolomite were strongly replaced by assemblages of hematite+rhodochrosite and hematite+kutnohorite/Mn-rich dolomite, respectively. In addition, siderite also experienced strong silicification. These changes were associated with the dissolution of associated sulfides (sphalerite, galena). The following portion of the vein contains low-Mn dolomite and calcite gangue with Zn-rich chlorite, wittichenite, tetrahedrite-group minerals, chalcopyrite, bornite, and djurleite, again showing common replacement textures in case of sulfides. The latest stage was characterized by the input of Ag and Hg, giving rise to Ag-Cu sulfides, native silver (partly Hg-rich), balkanite, and (meta)cinnabar. We explain the formation of hematite-bearing oxidized assemblages at the expense of pre-existing "normal" Příbram mineralization due to repeated episodic infiltration of oxygenated surface waters during the vein evolution. Episodic mixing of ore fluids with surface waters was suggested from previous stable isotope and fluid inclusion studies in the Příbram ore area. Our mineralogical study thus strengthens this genetic scenario, illustrates the dynamics of fluid movement during the evolution of a distinct ore vein structure, and shows that the low content of ore minerals cannot be necessarily a primary feature of a vein. [ABSTRACT FROM AUTHOR]

Background/Objectives: The present work proposes a mathematical model able to describe the dissolution of poly-disperse drug spherical particles in a solution (Dissolution Rate Test—DRT). DRT is a pivotal test performed in the pharmaceutical field to qualitatively assess drug bioavailability. Methods: The proposed mathematical model relies on the key hallmarks of DRT, such as particle size distribution, solubility, wettability, hydrodynamic conditions in the dissolving liquid of finite dimensions, and possible re-crystallization during the dissolution process. The spherical shape of the drug particles was the only cue simplification applied. Two model drugs were considered to check model robustness: theophylline (both soluble and wettable) and praziquantel (both poorly soluble and wettable). Results: The DRT data analysis within the proposed model allows us to understand that for theophylline, the main resistance to dissolution is due to the boundary layer surrounding drug particles, whereas wettability plays a negligible role. Conversely, the effect of low wettability cannot be neglected for praziquantel. These results are validated by the determination of drug wettability performed while measuring the solid–liquid contact angle on four liquids with decreasing polarities. Moreover, the percentage of drug polarity was determined. Conclusions: The proposed mathematical model confirms the importance of the different physical phenomena leading the dissolution of poly-disperse solid drug particles in a solution. Although a comprehensive mathematical model was proposed and applied, the DRT data of theophylline and praziquantel was successfully fitted by means of just two fitting parameters. [ABSTRACT FROM AUTHOR]

Hydraulic dissolution, driven by carbon dioxide-rich precipitation and runoff, leads to the gradual breakdown and removal of soluble rock materials, creating unique surface and subsurface features. Dissolution is a complex process that is related to numerous factors, and the complete simulation of its process is a challenging problem. On the basis of deep investigation of the theories of geology and rock geomorphology, this paper puts forward a method for simulating the dissolution phenomenon on a rock surface. Around the movement of water, this method carries out dissolution calculations, including processes such as droplet dissolution, water flow, dissolution, deposition, and evaporation. It also considers the lateral dissolution effect of centrifugal force when water flows through bends, achieving a comprehensive simulation of the dissolution process. This method can realistically simulate various typical karst landforms such as karst pits, karst ditches, and stone forests, with interactive simulation efficiency. [ABSTRACT FROM AUTHOR]

Empagliflozin (EFZ), a sodium-glucose co-transporter 2 (SGLT2) inhibitor used to treat type 2 diabetes, faces challenges with poor solubility and bioavailability. This study aimed to evaluate a Self-Nanoemulsifying Drug Delivery System (SNEDDS), specifically SN1C, for enhancing EFZ's dissolution rate and pharmacokinetics compared to pure EFZ powder and a marketed tablet (MKT). We assessed dissolution profiles in vitro and conducted pharmacokinetic studies in rats following oral administration of the three formulations. Plasma samples were analyzed using LC-MS/MS, and pharmacokinetic parameters were determined via non-compartmental analysis. SN1C demonstrated the highest dissolution rate in vitro. In vivo, SN1C achieved a significantly higher maximum plasma concentration (Cmax) and area under the curve (AUC(inf)) than EFZ and MKT, with approximately 1.5-fold higher Cmax and a significantly greater AUC(inf) (p < 0.05). Tmax and half-life (t1/2) were similar across all formulations, indicating that SNEDDS did not negatively impact these parameters. The results suggest that SN1C substantially improves the bioavailability of EFZ, highlighting the efficacy of SNEDDS technology in enhancing the oral delivery and therapeutic effectiveness of poorly soluble drugs like EFZ. [ABSTRACT FROM AUTHOR]

Magnesium potassium phosphate hexahydrate (MgKPO4·6H2O) was used as solidification matrix to immobilize some radioactive element and some heavy metal ions, the stability of MgKPO4·6H2O under different conditions had become the focus. This work gives new insights on the stability of synthesized MgKPO4·6H2O in the different temperatures and pH values solutions. The solid phase transformed from synthesized MgKPO4·6H2O was characterized by X‐ray diffractometer (XRD), thermal gravity analysis (TG/DSC), Fourier‐transform infrared spectrum (FTIR) and scanning electron microscope (SEM) at different temperature and pH values solution. Results indicated MgKPO4·6H2O had almost no phase transition at the temperature of 50°C and 60°C. Mg3(PO4)2·22H2O appears with the increase of solution temperature. The main phase is MgKPO4·6H2O at the pH of 9 and 12, minor MgHPO4·3H2O formed at the pH of 6, next Mg3(PO4)2·22H2O formed at the pH of 3 and 6. High pH value environment is beneficial for the maintenance of MgKPO4·6H2O. This study is an important guidance for the application of MgKPO4·6H2O crystal. [ABSTRACT FROM AUTHOR]

Enabling drug formulations are often required to ensure sufficient absorption after oral administration of poorly soluble drugs. While these formulations typically increase the apparent solubility of the drug, it is widely acknowledged that only molecularly dissolved, i.e., free fraction of the drug, is prone for direct absorption, while colloid-associated drug does not permeate to the same extent. In the present study, we aimed at comparing the effect of molecularly and apparently (i.e., the sum of molecularly and colloid-associated drug) dissolved drug concentrations on the oral absorption of a poorly water-soluble drug compound, Alectinib. Mixtures of Alectinib and respectively 50 %, 25 %, 12.5 %, and 3 % sodium lauryl sulfate (SLS) relative to the dose were prepared and small-scale dissolution tests were performed under simulated fed and fasted state conditions. Both the molecularly and apparently dissolved drug concentrations were assessed in parallel using microdialysis and centrifugation/filtration sampling, respectively. The data served as the basis for an in vitro-in vivo correlation (IVIVC) and as input for a GastroPlusTM physiologically-based biopharmaceutics model (PBBM). It was shown that with increasing the content of SLS the apparently dissolved drug in FeSSIF and FaSSIF increased to a linear extent and thus, the predicted in vivo performance of the 50 % SLS formulation, based on apparently dissolved drug, would outperform all other formulations. Against common expectation, however, the free (molecularly dissolved) drug concentrations were found to vary with SLS concentrations as well, yet to a minor extent. A systematic comparison of solubilized and free drug dissolution patterns at different SLS contents of the formulations and prandial states allowed for interesting insights into the complex dissolution-/supersaturation-, micellization-, and precipitation-behavior of the formulations. When comparing the in vitro datasets with human pharmacokinetic data from a bioequivalence study, it was shown that the use of molecularly dissolved drug resulted in an improved IVIVC. By incorporating the in vitro dissolution datasets into the GastroPlusTM PBBM, the apparently dissolved drug concentrations resulted in both, a remarkable overprediction of plasma concentrations as well as a misprediction of the influence of SLS on systemic exposure. In contrast, by using the molecularly dissolved drug (i.e., free fraction) as the model input, the predicted plasma concentration-time profiles were in excellent agreement with observed data for all formulations under both fed and fasted conditions. By combining an advanced in vitro assessment with PBBM, the present study confirmed that only the molecularly dissolved drug, and not the colloid-associated drug, is available for direct absorption. [Display omitted] [ABSTRACT FROM AUTHOR]

Predictive performance assays are crucial for the development and approval of nanomedicines and their bioequivalent successors. At present, there are no established compendial methods that provide a reliable standard for comparing and selecting these formulation prototypes, and our understanding of the in vivo release remains still incomplete. Consequently, extensive animal studies, with enhanced analytical resolution for both, released and encapsulated drug, are necessary to assess bioequivalence. This significantly raises the cost and duration of nanomedicine development. This work presents the development of a discriminatory and biopredictive release test method for liposomal prednisolone phosphate. Using model-informed deconvolution, we identified an in vivo target release. The experimental design employed a discrete L-optimal configuration to refine the analytical method and determine the impact of in vitro parameters on the dosage form. A three-point specification evaluated the key phases of in vivo release: early (T-5%), intermediate (T-20%), and late release behavior (T-40%), compared to the in vivo release profile of the reference product, NanoCort®. Various levels of shear responses and the influence of clinically relevant release media compositions were tested. This enabled an assessment of the effect of shear on the release, an essential aspect of their in vivo deformation and release behavior. The type and concentration of proteins in the medium influence liposome release. Fetal bovine serum strongly impacted the discriminatory performance at intermediate shear conditions. The method provided deep insights into the release response of liposomes and offers an interesting workflow for in vitro bioequivalence evaluation. [Display omitted] [ABSTRACT FROM AUTHOR]

Ni-WC composite coating was prepared on Q235 steel substrate by plasma transfer arc (PTA) with welding current ranging from 70 A to 85 A. The results show that the dissolution behaviour of WC particles and the elemental diffusion at the interface promoted by the increased welding current promote the formation and evolution of precipitates, including M 7 (B, C) 3 and M 6 C. The increased current reduced the volume fraction of WC particles in the coating, but increased that of the precipitates. At welding currents of 75 A and 80 A, dendritic-like M 7 (B, C) 3 presented a regular distribution at the bottom of the coating. At a welding current of 80 A, M 6 C phase began to form at the bottom of the coating. When the welding current reached 85 A, the dendritic structure was broken, and the M 6 C phase aggregated and grew. The Ni-WC coating had visible delamination. WC particles at the upper part of the coating dissolved more severely compared to those at the middle and bottom of the coating. Ni 3 Si compound was formed at the upper and middle of the coating, and it had a crystal orientation relationship of [011] Ni3Si ∥[011] γ-Ni , (11-1) Ni3Si ∥(11-1) γ-Ni , (−200) Ni3Si ∥(-200) γ-Ni , (-11-1) Ni3Si 1.3° from (-11-1) γ-Ni with γ-Ni. The average hardness of the coating decreased slightly due to the dissolution of WC, but the hardness at the interface increased, showing an improved bonding of the interface. The newly formed high hardness precipitates can share the load coming from the friction paired ball, thus reducing CoF and wear loss of the coating. [ABSTRACT FROM AUTHOR]

The article presents a kinetic model describing the lead vapor oxidation in the vapor bubble volume to produce lead oxide and hydrogen with their subsequent dissolution in the lead melt volume. The model is implemented in the approximation of homogeneous distribution of reagents and oxidation reaction products in the bubble volume. An analytical solution for stationary oxidation conditions is obtained. It is shown that vapor bubbles in the lead melt volume are a sort of chemical "microreactors" producing lead oxide and hydrogen, which subsequently dissolve in the melt volume. However, such hydrogen generation mechanism does not pose any threat for the primary coolant circuit of fast lead cooled reactors in terms of hydrogen accumulation and explosion hazard in view of essentially low intensity of the hydrogen generation source. The article presents the results of water to hydrogen conversion assessments carried out with the use of a homogeneous kinetic model for interaction of water vapor with lead vapor in the vapor bubble volume. The model incorporates mechanisms governing lead evaporation into the bubble volume, oxidation of lead vapor as it interacts with water vapor in the bubble volume, and dissolution of reaction products in the lead melt surrounding the bubble. One more important result of equilibrium thermodynamic computations is connected with a possible change in the composition of iron oxides in the melt after the injection of water from the steam generator leak into the melt. The ingress of water into the lead melt may cause a change in the composition of iron oxides, thereby increasing the fraction of hematite and decreasing the fraction of magnetite. This may entail a change in the composition of the protective oxide film on the structural steel surface to make it more brittle. [ABSTRACT FROM AUTHOR]

Currently, there are quite a few data on the ways silver nanoparticles get into the aquatic environment, on their subsequent dissolution in water, and on the release of toxic Ag+ ions. Differences in the experimental conditions hinder the determination of the basic regularities of this process. In this study, the stages of oxidative dissolution of AgNPs were studied, starting from the formation of silver hydrosol in deaerated solution, the reaction of silver with oxygen and with drinking and natural waters, the analysis of intermediate species of the oxidized colloidal particles, and the subsequent particle aggregation and precipitation, by optical spectroscopy, DLS, TEM, STEM, and EDX. In the presence of oxygen, silver nanoparticles undergo oxidative dissolution, which gives Ag+ ions and results in the subsequent aggregation of nanoparticles. The carbonate hydrosol loses stability when mixed with waters of various origin. This is due to the destruction of the electric double layer, which is caused by an increase in the solution's ionic strength and the neutralization of the charge of the metal core. The environmental hazard of the silver nanoparticle hydrosol would noticeably change and/or decrease when the nanoparticles get into natural waters because of their fast precipitation and because the major part of released Ag+ ions form poorly soluble salts with ions present in water. [ABSTRACT FROM AUTHOR]

The increasing global focus on carbon capture and storage (CCS) has highlighted the potential for offshore CO2 sequestration, particularly following recent successes in onshore projects. This research investigates the qualitative analysis of carbon trapping efficiency in offshore basins, employing a GEM simulator to incorporate factors such as aqueous solubility and geochemistry. The findings reveal that anticlines represent ideal geological structures for carbon storage, effectively trapping a significant portion of injected CO2. For effective mineralization, it is crucial to dissolve CO2 into saline aquifers to generate H+, which facilitates the release of Ca2+ and Al3+ from anorthite. This process leads to the dissolution of anorthite and the precipitation of kaolinite, while calcite transitions from a dissolved state to a precipitated state over time. The analysis indicates that structural trapping provides the highest storage contribution during the injection phase, whereas residual gas trapping becomes dominant by the end of the simulation. Notably, it is observed that the storage contribution of structural trapping decreases from 28.39% to 19.05%, and the percentage increase in storage contributions of residual gas, solubility, ionic, and mineral trapping are 4.12%, 3.25%, 1.69%, and 0.28% for CO2 plus water injection, thereby improving the long-term security of CO2 storage in offshore basins. It is most beneficial to optimize the layout and design of the injection well to ensure a uniform distribution of carbon dioxide and to increase the injection rate. [ABSTRACT FROM AUTHOR]

This investigation focuses on the prevalent continental oil shale within the Triassic Chang 7, a member of the Yanchang Formation in the Ordos Basin and the Permian Lucaogou Formation in the Junggar Basin of western China, and delves into the impacts of hydrocarbon generation and the derived organic acids on the physical attributes of oil shale reservoirs. Water-soluble organic acids (WSOAs) were extracted via Soxhlet extraction and analyzed by a 940 ion chromatograph (Metrohm AG), supplemented with core observations, thin-section analyses, pyrolysis, and trace element assays, as well as the qualitative observation of pore structures via FIB-SEM scanning electron microscopy. The study discloses substantial disparities in the types and abundances of organic acids within the oil shale strata of the two regions, with mono-acids being conspicuously more prevalent than dicarboxylic acids. The spatial distribution of organic acids within the oil shale strata in the two regions is non-uniform, and their generation is inextricably correlated with the type of organic matter, thermal maturity, and depth at which they are buried. During diverse stages of diagenesis, the hydrocarbons and organic acids produced from the pyrolysis of organic matter not only exert an impact on the properties of pore fluids but also interact with diagenetic processes such as compaction, dissolution, and metasomatism to enhance the reservoir quality of oil shale. The synergy between chemical interactions and physical alterations collectively governs the migration and distribution patterns of organic acids as well as the characteristics of oil shale reservoirs. Furthermore, the sources of organic acids within the oil shale series in the two regions demonstrate pronounced dissimilarities, which are intimately associated with the peculiarities of their sedimentary milieu. The oil shale of the Yanchang Formation was formed in a warm and humid freshwater lacustrine basin environment, while the oil shale of the Lucaogou Formation was deposited in a brackish to saline lacustrine setting under an arid to semi-arid climatic regime. These variances not only illuminate the intricacy and multiplicity of the sedimentary attributes of oil shale but also accentuate the impact of the sedimentary environment on the genesis and distribution of organic acids, especially the transformation and optimization of reservoir dissolution by organic acids generated during hydrocarbon generation—a factor of paramount significance for the precise identification and effective development of the "sweet spot" area of shale oil. These areas, characterized by an abundance of organic matter, their maturity, and superior reservoir properties, are the foci of the efficient exploration and development of continental shale oil. [ABSTRACT FROM AUTHOR]

The present study was aimed to ameliorate the issue of solubility and thereby, bioavailability of ketoprofen, a BCS Class II drug. The sustained release matrix tablets (MT) were prepared using surfactant-assisted wet granulation (SAWG) with 1–5% of different surfactants. The tablet characteristics were within the compendial limits. The selected sustained release-compliant matrix tablet formulation containing granules prepared using 3% Soluplus® (MT2) released the drug by swelling-erosion. In human volunteers, MT2 attained the maximum plasma concentration (Cmax) of 5.72µg /ml ± 0.30 h, time to Cmax (Tmax) of 5.56 ± 0.30 h and maintained the plasma concentration above its minimum effective concentration (MEC), 0.7 µg.ml−1 till 24h. A control formulation, prepared from granules without surfactant (MT16), promptly attained Cmax of 9.62 ± 0.76 µg/ml within 1h but rapidly declined to below MEC in 8h. Area under the curve from initial point to infinity (AUC0-∞) of MT2 (78.65 ± 7.64 µg.h.ml−1) was 2.29 folds higher than 34.39 ± 3.06 µg.h.ml−1 of MT16. With decreased Cmax, increased AUC0-∞, delayed Tmax and retained ketoprofen concentration above MEC for longer time, MT2 corresponded with the in-vitro sustained drug release characteristic. There is a likelihood of administration of once-a-day single dose of MT2 without plasma fluctuations, expected from two doses of MT16. SAWG helped developing a swellable-erodible sustained release matrix tablet formulation of ketoprofen with the desired biopharmaceutical and pharmacokinetics properties, merely by addition of Soluplus® in granules and without incorporation of any special ingredients or the major manipulation of the formulative ingredients in the formulation. [ABSTRACT FROM AUTHOR]

The focus of current studies was to fabricate dose flexible printlets of dapsone (DDS) for pediatric patients by selective laser sintering (SLS) 3D printing method, and evaluate its physicochemical, patient in-use stability, and pharmacokinetic attributes. Eight formulations were fabricated using Kollicoat® IR, Eudragit® L-100-55 and StarCap®as excipients and evaluated for hardness, disintegration, dissolution, amorphous phase by differential scanning calorimetry and X-ray powder diffraction, in-use stability at 30 oC/75% RH for a month, and pharmacokinetic study in Sprague Dawley rats. The hardness, and disintegration of the printlets varied from 2.6±1.0 (F4) to 7.7±0.9 (F3) N and 2.0±0.4 (F2) to 7.6±0.6 (F3) sec, respectively. The drug was partially present as an amorphous form in the printlets. The drug was completely (>85%) dissolved in 20 min. No change in drug form or dissolution extent was observed after storage at in use condition. Pharmacokinetic profiles of both formulations (tablets and printlets) were almost superimposable with no statistical difference in pharmacokinetic parameters (Tmax, Cmax, and AUC0-¥)between formulations (p>0.05). Values of EC50 (half maximal effective concentration) and EC90 (maximal concentration inducing 90% maximal response) were 0.50±0.15 and 1.32±0.26 mM, 0.41±0.06 and 1.11±0.21, and 0.42±0.13 and 1.36±0.19 mM for DDS, printlet and tablet formulations, respectively, and differences were statistically insignificant (p>0.05). In conclusion, tablet and printlet formulations are expected to be clinical similar, thus clinically interchangeable. [ABSTRACT FROM AUTHOR]

The intricate process of protein binding orchestrates crucial drug interactions within the bloodstream, facilitating the formation of soluble complexes. This research endeavours to improve the dissolution and oral bioavailability of Rifampicin (RMP) by strategically manipulating drug-protein binding dynamics and the hydrophobic characteristics of human serum albumin (HSA). Various precipitation techniques leveraging methanol, ammonium sulfate, and heat treatment were meticulously employed to tailor the properties of colloidal albumin (HSA NPs). The resultant complexes underwent comprehensive characterization encompassing evaluations of hydrophobicity, size distribution, surface charge, and structural analyses through FTIR, TG-DSC, XRD, and morphological examinations. The findings revealed a significant binding affinity of 78.07 ± 6.6% with native albumin, aligning with prior research. Notably, the complex RMP-HSA NPs-M13, synthesized via the methanolic precipitation method, exhibited the most substantial complexation, achieving a remarkable 3.5-fold increase, followed by the ammonium sulfate (twofold) and heat treatment (1.07-fold) methods in comparison to native albumin binding. The gastric simulated media exhibited accelerated drug release kinetics, with maximal dissolution achieved within two hours, contrasting with the prolonged release observed under intestinal pH conditions. These findings translated into significant improvements in drug permeation, as evidenced by pharmacokinetic profiles demonstrating elevated Cmax, AUC, t1/2, and MRT values for RMP-HSA NPs-M13 compared to free RMP. In summary, this innovative approach underscores the potential of precipitation methods in engineering stable colloidal carrier systems tailored to enhance the oral bioavailability of poorly soluble drugs, offering a pragmatic and scalable alternative to conventional surfactants, polymers, or high-energy methods for complex formation and production. Highlights: Colloidal albumin produced by methanol exhibits superior physiochemical and pharmaceutical performance. Albumin-Rifampicin conjugates are thought to be a potential method for improving drug release and oral bioavailability. Albumin-Rifampicin complex shows better pharmacokinetic characteristics compared to free Rifampicin. [ABSTRACT FROM AUTHOR]

The dissolution (introduced by Isbell in [3], discussed by Johnstone in [5] and later exploited by Plewe in [12, 13]) is here viewed as the relation of the geometry of L with that of the more dispersed T(L) = S(L)op mediated by the natural embedding and its adjoint localic map γL: T(L) → L. The associated image-preimage adjunction (γL)−1 [−] ⊣ γL [−] between the frames T(L) and TT(L) is shown to coincide with the adjunction cT(L) ⊣ γT(L) of the second step of the assembly (tower) of L. This helps to explain the role of T(L) = S(L)op as an "almost discrete lift" (sometimes used as a sort of model of the classical discrete lift DL → L) as a dispersion going halfway to Booleanness. Consequent use of the concrete sublocales technique simplifies the reasoning. We illustrate it on the celebrated Plewe's theorem on ultranormality (and ultraparacompactness) of S(L) which becomes (we hope) substantially more transparent. [ABSTRACT FROM AUTHOR]

Phosphorus plays a multifaceted role for all known life and hence understanding its sources on the early Earth provides constraints on how life developed to incorporate this element into its biochemistry. Currently, the major phosphorus mineral group on the surface of the Earth are the apatites, which are poorly soluble calcium phosphates and hence may not have been a good source of phosphorus on the early Earth. An alternative source of phosphorus may be the mineral olivine. Given that olivine makes up a large part of the upper mantle of Earth and presumably other rocky planets and moons, it stands to reason that olivine may be a potential phosphorus reservoir for prebiotic chemical environments. Here we examine the phosphorus content of 10 olivine samples from different terrestrial localities to determine their P content and P speciation. We find that extracts of the samples contain varying amounts of phosphate, and some contain pyrophosphate. Olivine may have served as a source of phosphate on the early Earth and possibly elsewhere in the solar system, and its dissolution could have supplied this nutrient to a nascent biosphere. [ABSTRACT FROM AUTHOR]

Uncontrollable growth of Zn dendrites, irreversible dissolution of cathode material and solidification of aqueous electrolyte at low temperatures severely restrict the development of aqueous Zn‐ion batteries. In this work, 2,2,2‐trifluoroethanol (TFEA) with a volume fraction of 50% as a highly compatible polar‐solvent is introduced to 1.3 M Zn(CF3SO3)2 aqueous electrolyte, achieving stable high‐performance Zn‐ion batteries. Massive theoretical calculations and characterization analysis demonstrate that TFEA weakens the tip effect of Zn anode and restrains the growth of Zn dendrites due to electrostatic adsorption and coordinate with H2O to disrupt the hydrogen bonding network in water. Furthermore, TFEA increases the wettability of the cathode and alleviates the dissolution of V2O5, thus improving the capacity of the full battery. Based on those positive effects of TFEA on Zn anode, V2O5 cathode, and aqueous electrolyte, the Zn//Zn symmetric cell delivers a long cycle‐life of 782 h at 5 mA cm−2 and 2 mA h cm−2. The full battery still declares an initial capacity of 116.78 mA h g−1, and persists 87.73% capacity in 2000 cycles at −25 °C. This work presents an effective strategy for fully compatible co‐solvent to promote the stability of Zn anode, V2O5 cathode and aqueous electrolyte for high‐performance Zn‐ion batteries. [ABSTRACT FROM AUTHOR]

Hydroxyapatite and β-tricalcium phosphate are the most popular calcium phosphates used for bone tissue regeneration and in the manufacture of prostheses for bone replacement. Incorporation of different ions in low concentrations into the crystal lattice of calcium phosphates allows enhancing or modifying their properties. In this work, stoichiometric hydroxyapatite, calcium deficient hydroxyapatite and β-tricalcium phosphate co-substituted with zinc, magnesium, and silicate were synthesized using a mechanochemical approach. The compositions of the materials were investigated by powder X-ray diffraction, FTIR spectroscopy and scanning electron microscopy. The materials prepared were assessed for dissolution in water and implanted into rat skull bones. For the first time, it was demonstrated that the substituted calcium-deficient hydroxyapatite has an increased solubility in water compared with β-tricalcium phosphate and hydroxyapatite. In vivo studies revealed that the calcium-deficient hydroxyapatite promotes better osteogenesis than other calcium phosphates investigated here, showing almost complete remodeling of the damaged bone tissue already after 5 months. In this regard, calcium-deficient hydroxyapatite with zinc, magnesium, and silicate substitution is the most promising material for bone tissue regeneration. [ABSTRACT FROM AUTHOR]

Additive manufacturing of pharmaceutical formulations offers advanced micro-structure control of oral solid dose (OSD) forms targeting not only customised dosing of an active pharmaceutical ingredient (API) but also custom-made drug release profiles. Traditionally, material extrusion 3D printing manufacturing was performed in a two-step manufacturing process via an intermediate feedstock filament. This process was often limited in the material space due to unsuitable (brittle) material properties, which required additional time to develop complex formulations to overcome. The objective of this study was to develop an additive manufacturing MicroFactory process to produce an immediate release (IR) OSD form containing 250 mg of mefenamic acid (MFA) with consistent drug release. In this study, we present a single-step additive manufacturing process employing a novel, filament-free melt extrusion 3D printer, the MicroFactory, to successfully print a previously 'non-printable' brittle Soluplus®-based formulation of MFA, resulting in targeted IR dissolution profiles. The physico-chemical properties of 3D printed MFA-Soluplus®-D-sorbitol formulation was characterised by thermal analysis, Fourier Transform Infrared spectroscopy (FTIR), and X-ray Diffraction Powder (XRPD) analysis, confirming the crystalline state of mefenamic acid as polymorphic form I. Oscillatory temperature and frequency rheology sweeps were related to the processability of the formulation in the MicroFactory. 3D printed, micro-structure controlled, OSDs showed good uniformity of mass and content and exhibited an IR profile with good consistency. Fitting a mathematical model to the dissolution data correlated rate parameters and release exponents with tablet porosity. This study illustrates how additive manufacturing via melt extrusion using this MicroFactory not only streamlines the manufacturing process (one-step vs. two-step) but also enables the processing of (brittle) pharmaceutical immediate-release polymers/polymer formulations, improving and facilitating targeted in vitro drug dissolution profiles. [ABSTRACT FROM AUTHOR]

The electrochemical applications of gold span the entire pH spectrum. Recently, gold dissolution in acidic and alkaline media has been studied, but less attention has been given to electrolytes at intermediate pH values. To address this gap, this work uses on‐line electrochemical dissolution inductively coupled plasma mass spectrometry (ICP‐MS) to examine gold dissolution across a pH range of 1 to 12.7 using phosphate buffer solutions. All experimental parameters, except pH, are kept constant, enabling a clear investigation of pH effects on anodic (gold oxidation) and cathodic (gold oxide reduction) dissolution processes. Results show that dissolution amounts are lowest at neutral pH values between 3 and 7, varying with the applied potential and exposure time. Anodic and cathodic dissolution dominate in acidic and alkaline electrolytes, respectively. Depending on the highest applied potentials and time exposure, the main dissolution mechanism shifts at pH=5, 7, and 9. The pH dependence of Au dissolution is proposed to be linked to the nature of gold oxides formed, the kinetics of oxide formation/reduction, gold ion redeposition, and the influence of the oxygen evolution reaction (OER) on dissolution. These results provide fundamental insights into gold dissolution under neutral pH conditions. [ABSTRACT FROM AUTHOR]

Background: Herbal medicines used for male sexual disorders are widespread across the globe and have been noted as likely candidates for adulteration. To assure access to safe and quality herbal products, this study aimed at sampling some herbal capsules indicated for male vitality for quality analytical checks. Methods: Herbal capsules sampled from two regions were subjected to physicochemical assessment, using pharmacopeial and regulatory standards. Microbial quality analysis was also performed on the selected products. A validated HPLC method for simultaneous analysis of sildenafil citrate and tadalafil was used to detect and quantify the possible presence of phosphodiesterase inhibitors in the selected products. Results: Out of a total of 57 herbal capsules, 19 were indicated for male sexual related illnesses of which only 8 fulfilled the inclusion criteria of being used exclusively for male vitality. The majority (62.5%) of the herbal products failed the weight uniformity test but all of them disintegrated within the acceptable limit of 30 min. The moisture and heavy metal contents were within limits of acceptability. Majority (87.5%) of the herbal products failed the test for the aerobic bacteria count; however, none of the isolated bacteria was pathogenic. Sildenafil citrate was detected in the majority (87.5%) of the herbal products in concentrations of 0.98–33.95 mg/g. Two products contained both sildenafil and tadalafil. High batch-to-batch variability was recorded in some physicochemical parameters and pharmaceutical adulterants. Conclusion: High incidence of quality fails and adulteration of herbal capsules for sexual disorders observed means there is a real risk of unintended dosing with phosphodiesterase inhibitors. This represents a public health issue and necessitates tighter monitoring of production standards by the regulator. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) are biocompatible materials with excellent anion exchange properties, making them suitable for use as drug carriers by incorporating the drug in its anionic form within their layered structure. In this study, an LDH was synthetized through ion exchange with valproate (VAL), an anticonvulsant drug, using an LDH with nitrate as the parent material. The resulting LDH-VAL sample underwent a comprehensive multi-technique characterization using XRD, TG-DSC, TEM, SEM, EDS, FTIR, XPS and zeta potential measurements. Dissolution kinetics and VAL release kinetics in an ample range of pH (3–9), along with biological assays to test biocompatibility, were also performed. All techniques confirmed the successful intercalation of the drug into the LDH structure, displacing all the nitrate ions of the parent material and increasing the basal spacing d 003 from 8.8 Å to 18.3 Å. VAL release in NaCl and physiological buffer solutions was incongruent with LDH dissolution, clearly indicating that VAL release was controlled by an ion exchange process. In 0.9 % NaCl solutions, 90–100 % of VAL was released with only 15–20 % of LDH dissolution, and in buffer solutions 100 % of VAL was released with, at the most, 30 % of LDH dissolution. Biological assays, including lactate dehydrogenase activity, serum calcium concentration and histological analysis of blood samples, confirmed that the prepared LDH-VAL is a biocompatible material with a potential use as a nanodrug carrier. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to the limitation of the subsequent process for producing V 2 O 5 , the converter of vanadium extraction needs to use the slag with high MgO content to splash slag. This paper focus on the corrosion behavior of vanadium slag with high MgO content on MgO–C refractory. Corrosion experiment, SEM-EDS analysis, XRF analysis, and theoretical calculation are utilized to study the interface and mass transfer between slags and refractory. The results indicate that the average width of the reaction interface decreases from 9.3 μm to 3 μm with the increase of MgO content from 2 wt % to 8 wt %. When the corrosion time increases from 15 min to 60 min, the average width of the reaction interface decreases from 9 μm to 5 μm, and stabilizes at 5 μm as the corrosion continues. The mass transfer coefficient of MgO rises to 0.663 × 10−2 cm s−1 in the first 60 min of corrosion time, and then falls to 0.592 × 10−2 cm s−1 as the corrosion continues to 120 min. The mass transfer coefficient of MgO also shows an increasing trend with the increase of temperature and rotation speed. When the temperature increases from 1445 °C to 1490 °C, the mass transfer coefficient of MgO increases from 0.1313 × 10−2 cm‧s−1 to 1.4556 × 10−2 cm‧s−1. When the rotation speed increases from 10 rpm to 30 rpm, the mass transfer coefficient of MgO increases from 0.411 × 10−2 cm s−1 to 0.818 × 10−2 cm s−1. [ABSTRACT FROM AUTHOR]

The advanced in silico simulation tools, such as physiologically based biopharmaceutics models (PBBM) or physiologically based pharmacokinetic models (PBPK), play critical role in model informed formulation development. This approach has been successfully implemented in the present case for development of novel omeprazole delayed-release orally disintegrating tablets (ODT) formulation, aimed to enhance patient compliance. PBBM was developed using physicochemical, biopharmaceutical, and dissolution data. The dissolution studies for pilot formulations were conducted in biopredictive media in fasting (0.1 N HCl followed by pH 6.8) and fed (pH 5 followed by pH 6.8) conditions. The model was extensively validated in three stages: pilot fasted, pilot fed virtual bioequivalence and food effect assessments. Impressively, the model was able to predict both passed and failed batches appropriately. Based on insights from the pilot study, a higher scale pivotal formulation was optimised. Prospective predictions were made for pivotal formulations using validated model and bio results were found to be in line with model predictions in fasting condition. Overall, a rationale and patient compliant formulation was developed using innovative modelling approach and filed to regulatory agency. The novel omeprazole formulation enhanced patient compliance through ease of administration thereby circumventing challenges of conventional formulation. [ABSTRACT FROM AUTHOR]

In soils managed to have adequate to high Mehlich‐3 phosphorus (P) concentrations throughout the US Maize Belt, the majority of crop P is soil‐derived. Struvite, a low water solubility ammonium phosphate fertilizer, may be therefore substituted for relatively high water‐soluble monoammonium phosphate (MAP) without adversely impacting maize (Zea mays L.) P uptake and growth, while minimizing fertilizer P loss risk. We determined the relative contribution of struvite and MAP to maize P uptake and soil solution P in soils representative of the US Maize Belt by radiolabelling fertilizers with 33P. We found 8% (struvite) to 22% (MAP) of early‐to‐mid vegetative growth stage (V7) maize P was fertilizer‐derived, and thus, 78%–92% was soil‐derived. Despite similar aboveground P uptake and maize growth, maize P use efficiency (PUE) determined directly by 33P was <5% for MAP (4.9%) and struvite (1.9%) indicating that in soils with adequate to high crop‐available P, early season fertilizer PUE is relatively low. If prorated to harvest stage, in‐season PUE was estimated to be 8% for struvite and 20% for MAP. MAP and struvite did not differ in relative contributions to water‐extractable P, a proxy for P loss risk, potentially reflecting lag effects in struvite P dissolution and/or the relatively fine particle size of synthesized fertilizers (<0.1 mm diameter). Since maize aboveground biomass and P uptake were similar for both struvite and MAP, struvite could be an effective P fertilizer for soils with adequate to high Mehlich‐3 P concentrations common across the US Maize Belt. [ABSTRACT FROM AUTHOR]