Due to their appealing physiochemical properties, particularly in the pharmaceutical industry, deep eutectic solvents (DESs) and ionic liquids (ILs) are utilized in various research fields and ...industries. The presented research analyzes the thermodynamic properties of a deep eutectic solvent created from natural molecules, menthol and lauric acid in a 2:1 molar ratio, and an ionic liquid based on two active pharmaceutical ingredients, benzocainium ibuprofenate. Initially, the low solubility of benzocainium ibuprofenate in water was observed, and a hydrophobic natural deep eutectic mixture of menthol:lauric acid in a 2:1 ratio was prepared to improve benzocainium ibuprofenate solubility. In order to determine the solvent properties of DESs and ILs mixtures at different temperatures and their molecular interactions to enhance the solvent performance, the apparent molar volume, limiting apparent molar expansibility, and viscosity B coefficient were estimated in temperature range from 293.15 K to 313.15 K and varying concentration of benzocainium ibuprofenate.
The present work focuses on modifying a local anaesthetic drug procaine into an ionic liquid and evaluating the resulting thermal behaviour and structural changes. Counter ions, salicylate, ...ibuprofenate, and docusate, were chosen due to different hydrogen-bonding abilities, molecular size, charge distribution, and functional groups. After synthesis of procaine salicylate, procaine ibuprofenate, and procaine docusate, spectroscopic investigations were performed using infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy to confirm proton transfer. Differential scanning calorimetry (DSC) and thermogravimetric (TG) analysis were used to determine the obtained ionic liquids' thermal behaviour. Experimental measurements of density, viscosity, and electrical conductivity were performed to get insight into the interactions occurring in the obtained ionic liquids. The viscosity and electrical conductivity data were analysed using the Vogel-Fulcher-Tammann (VFT) equation, while thermal expansion coefficients were calculated from measured density data. The obtained results found that the synthesised procaine salicylate and procaine docusate an ionic liquid's behaviours, including weak intermolecular forces, while procaine ibuprofenate showed more liquid co-crystal behaviour due to the absence of proton transfer for ibuprofen. In a theoretical phase of the investigation, the density functional theory (DFT) and molecular dynamics (MD) calculations were conducted. The obtained descriptors and radial distribution functions were used to analyse the interactions between ions of synthesised ionic liquids. In addition, solubility determination results proved that procaine transformation into procaine salicylate and procaine ibuprofenate ionic liquids enhanced its solubility in water, while procaine docusate reduces procaine solubility.
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The rapid and sensitive voltammetric determination of organic UV filters benzophenone-3 (BP-3) and avobenzone (AVO) was performed by an ionic liquid carbon paste electrode (IL-CPE). Namely, the ...synthesized pyridinium-based ILs, 1-butyl-3-methylpyridinium chloride (N–C4–3C1PyCl) and 1-ethoxyethyl-3-methylpyridinium chloride (N–C2OC2–3C1PyCl) were compared as bulk CPE modifiers for BP-3 determination. N–C4–3C1PyCl-CPE showed more favorable interactions with the target analyte, and it was tested for AVO determination, too. Cyclic voltammetric (CV) studies suggested that the irreversible electrode reaction is adsorption controlled in the case of both UV filters. Also, the square-wave adsorptive stripping voltammetric (SW-AdSV) method was optimized for quantifying selected UV filters. In the model solutions, the linear calibration curve was obtained by the SW-AdSV method in the concentration range from 0.05 to 0.89 μg mL−1 at pH 3.0 for BP-3 (Eacc = −0.7 V, tacc = 100 s), and from 0.05 to 1.77 μg mL−1 at pH 11.98 for AVO (Eacc = 0.2 V, tacc = 100 s). The evaluated limit of detection (LOD) was 0.015 μg mL−1 in both cases, while the relative standard deviation (RSD) was lower than 1.5%. The affordable IL-based voltammetric sensor fulfills the main requirements for application in real samples due to an adequate selectivity towards selected analytes in the presence of interferents usually found in swimming pool water. Therefore, the BP-3 and AVO were quantified in a swimming pool water matrix with good repeatability and recovery. The obtained results demonstrate an excellent potential of the IL-CPEs, especially of the N–C4–3C1PyCl-CPE, for determining selected UV filters in various real samples.
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•Pyridinium-based ionic liquids were used for carbon paste electrode modification.•Simple and reliable SW-AdSV method for selected UV filters sensing was developed.•Achieved LOD for benzophenone-3 (BP-3) and avobenzone (AVO) was 0.015 μg mL−1.•N–C4–3C1PyCl-CPE enables determination of BP-3 and AVO in swimming pool water sample.•Good repeatability and high selectivity towards UV filters sensing were obtained.
•Aqueous solutions of metformin and artificial sweeteners of varying molalities were created.•Density, sound velocity and viscosity measurements of the solutions were performed from 278.15 to ...318.15 K.•Metformin solutions with Na-saccharin and acesulfame-K behave differently.•Metformin has strong interactions with water, acts as a structure maker in all three systems.•The addition of artificial sweeteners did not significantly improve taste.
Measurements of the density, sound velocity, and viscosity of metformin hydrochloride (MetHCl) solutions in water and 0.1 mol∙kg−1 aqueous solution of sodium saccharin (Na-Sah) and acesulfame potassium (Ace-K) were carried out over the concentration range up ∼ 0.16 mol∙kg−1 to MetHCl at nine temperatures T = (278.15, 283.15, 288.15, 293.15, 298.15, 303.15, 308.15, 313.15, 318.15) K. Several physicochemical properties of these systems were determined from the experimental data, including apparent molar volumes, apparent molar volumes at infinite dilution, finite apparent molar volumes of transfer, apparent specific volumes at infinite dilution, apparent molar isentropic compressibility at infinite dilution, hydration numbers, viscosity B coefficients, and thermodynamic parameters of viscous flow. The results were further discussed in terms of solute–solvent and solute–solute interactions to enlighten the interactions of metformin with artificial sweeteners in water and the possibility that artificial sweeteners mask the bitter taste of metformin.
The purpose of this paper was to examine the density, viscosity and electrical conductivity at different temperatures, as well as the thermal stability and structural properties of previously ...reported ionic liquids based on active pharmaceutical ingredients. Lidocaine-based ionic liquids, with ibuprofen and salicylate as counterion, were prepared first. Their structures were confirmed by infrared, mass and
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H and
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C nuclear magnetic resonance spectroscopy. The Newtonian behaviour of lidocaine ibuprofenate was confirmed from viscosity measurement results, while it was impossible to determine for lidocaine salicylate. The interactions and structures of the studied ionic liquids were analyzed based on the measured density values, viscosity, electrical conductivity, and calculated values of thermal expansion coefficients and activation energy of viscous flow. From a theoretical aspect, DFT and MD calculations were performed. The obtained descriptors and radial distribution, as well as structural functions, were used to understand the structural organization of the synthesized ionic liquids.
A detailed theoretical and physico-chemical investigation of synthesized pharmaceutically active ionic liquids.
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•Nanofibers with loaded ionic liquid were successfully produced.•Rised IL content reduce viscosity and increase conductivity electrospinning solution.•PEO-IL nanofibers' average ...diameter decreased with the increased IL content.•Thicker nanofibers were obtained with a higher molecular weight polymer.•Abcence of hydrogen bonds between ILs and PEO in electrospun nanofibers.
Keeping up with cutting edge research in the field of drug delivery, the overall goal of this study was to develop innovative electrospun nanofibers loaded with ionic liquids (ILs) as active pharmaceutical ingredients (APIs). For the first time, a novel approach was examined by combining biocompatible polymer, poly (ethylene oxide) (PEO), and pharmaceutical ILs in an electrospinning process to develop nanofibers with high drug loading (up to 47%). Firstly, two well-known local anaesthetic drugs, lidocaine and procaine, were modified into ILs with the salicylate, forming lidocaine salicylate and procaine salicylate. Its dual-functional nature and increased water solubility for 4- to 10-fold depending on the drug used contribute to overcoming current hurdles encountered by APIs such as poor solubility, low bioavailability, and polymorphism of the solid-state. Nanofibers were formulated using solutions tested for density, viscosity, electrical conductivity, and small-angle X-ray scattering by varying PEO molecular weight and the PEO to IL mass ratio. Scanning electron microscopy showed the surface morphology of the obtained nanofibers, while Fourier transform infrared spectroscopy and differential scanning calorimetry confirmed IL in the nanofibers in an amorphous state. Thus, nanofibers with incorporated IL represent well-known drugs in the new form and a novel dermal application delivery system.
•1-Butyl-3-methylimidazolium salicylate reduces the bitter taste and increases the solubility of caffeine in water.•The caffeine molecule in BmimSal aqueous solution is an anomalous ...structure-maker.•π-π interactions between caffeine and salicylate molecules occur at higher temperatures.•BMIM+ cation stabilize the salicylate anion enabling its more uniform position around the caffeine molecule.
In this study, a detailed physicochemical characterization of caffeine in 0.1 mol∙kg−1 of 1-butyl-3-methylimidazolium salicylate (abbreviation BmimSal) aqueous solutions is performed based on density, speed of sound, refractive index and viscosity measurements in the temperature range from T = (293.15–313.15) K. BmimSal slightly increases the solubility of caffeine in water. Data obtained from the volumetric and viscosimetric measurements indicate that BmimSal promotes the self-aggregation of caffeine in water. Molecular dynamic simulations provided insight into how BmimSal increases caffeine solubility in water. At higher temperatures, the salicylate anion has stronger interactions with caffeine through π–π interactions than at lower temperatures.
Tetracainium salicylate and tetracainium ibuprofenate were synthesized as active pharmaceutical ingredient ionic liquids (API-ILs). These ILs represent a combination of a drug for local anaesthesia ...(tetracaine) and nonsteroidal anti-inflammatory drugs (salicylic acid and ibuprofen). After IL synthesis, spectroscopic investigations were performed using infrared and nuclear magnetic resonance spectroscopy to confirm their structures. Differential scanning calorimetry and thermogravimetric analysis determined the obtained thermal behaviour of the ionic liquids. Experimental density, viscosity, and electrical conductivity measurements were performed in a wide temperature range to understand the interactions occurring in the obtained pharmaceutically active ionic liquids. All experimental values were well-fitted by the empirical equations. According to the theoretical calculations, weaker interactions of tetracaine with ibuprofenate than with salicylate are found, ascribed to the decreasing molecular symmetry, weakened hydrogen bonding, and increasing steric hindrance of ibuprofenate's alkyl chain.
Evolution of physicochemical parameters such as thermal stability, density, viscosity and electrical conductivity at various temperatures for two pharmaceutically active ionic liquids - tetracainium salicylate and tetracainium ibuprofenate.
•Stronger ion-ion attraction in the procaine salicylate aqueous solution than in lidocaine salicylate.•Almost the same hydration number, but a significant difference in the organisation of water ...molecules around cations.•NH2 group attached to the procaine benzene ring significantly induce its hydrophilic properties.•Partially zwitter-ionic form of lidocaine amide group is better hydrated than the procaine ester group.•The tendency of cation-cation interactions between positively charged nitrogen and ester group in procaine.
Ion-ion and ion–solvent interactions have been investigated in the aqueous solutions of two drug-based ionic liquids, lidocaine salicylate and procaine salicylate, from density, viscosity, molar conductivity and computational simulations studies. The density and viscosity results were fitted with the Masson and the Jones-Dole equations, respectively. Ultra-high accurate conductometric measurements were combined with the low-concentration chemical model to derive values of limiting molar conductivities, λo, limiting molar conductivity of the cations, λ+o, and association constants, KA, for examined ionic liquids at different temperatures. From the obtained thermodynamic parameters and the molecular dynamics study, stronger attraction between ions and slightly higher structure making ability in the aqueous solution of procaine salicylate was noted. A detailed insight into the ion’s interactions was analysed from the difference between the amide and ester functional group and the side groups attached to the benzene ring of cations. Based on the obtained results, the potential use of these ILs as transdermal local anaesthetic drugs was discussed.
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•Mixtures of benzocainium ibuprofenate in menthol:decanoic acid with molar ratios of 1:2, 1:1 and 2:1 were prepared.•More pronounced solvation ability of system with an excess of ...decanoic acid (Men:DecA/1:2) than the other systems.•System with excess decanoic acid leaves the possibility that its excess makes interactions with the ionic liquid.•The presence of benzocainium ibuprofenate increases structural organization in all three NADES systems.
In this work, the mixture of the active pharmaceutical ingredient ionic liquid (API-IL) benzocainium ibuprofenate and natural deep eutectic solvents (NADESs) of menthol:decanoic acid with the molar ratios 1:2, 1:1 and 2:1 were prepared, and nature of interactions in these systems was investigated for the first time. These systems of hydrophobic API-IL-NADES are mixtures that are compatible and offer an opportunity for the topical application of ionic liquids, which are in a liquid state above room temperature and do not dissolve in water well. Ionic liquid and NADESs with different molar ratios were synthesized and characterized using infrared and nuclear magnetic resonance spectroscopy and differential scanning calorimetry. The densities, speeds of sound, and viscosities of the studied mixtures were measured in the temperature range from T = (293.15 to 318.15) K at different API-IL molalities. From obtained thermodynamic properties, it was discussed how the mole fraction of the NADES components influences the molecular and solvent performance.
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