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.
In this work, previously prepared protic ionic liquids (PILs) with 1-ammonium-2-propanol cations and five different anions, acetate, trichloroacetate, chloroacetate, 3-chloropropionate, and ...4-chlorobutyrate, and their aqueous solutions were characterized. Densities of ionic liquids (ILs) and their diluted aqueous solutions have been measured over the whole composition range at selected temperatures from T = 293.15 to 353.15 K for pure ILs and from T = 293.15 to 313.15 K for diluted aqueous solutions and at atmospheric pressure (p = 0.1 MPa). The influence of specific functional groups on the anion structure, density, volumetric properties, and the nature of interactions in aqueous solutions has been discussed. Several well-known techniques and criteria, such as volumetric quantities, Hepler’s coefficient, or expansibility of the ions, were used to explain water structuring and the nature of interactions in the aqueous solutions of studied PILs and classify them as the structure-making (cosmotropes) or structure-breaking (chaotropes) substances.
Densities, viscosities, and electrical conductivities were determined and discussed for a binary mixture containing 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid, ...bmpyrrNTf2, and diethyl carbonate (DEC) as a function of temperature (T = 293.15–323.15 K) at atmospheric pressure (p = 0.1 MPa) over the entire range composition. Based on experimental density data, the related excess molar volumes were calculated and fitted using Redlich–Kister’s polynomial equation. The Casteel–Amis equation was used to correlate data obtained from electrical conductivity measurements. The effect of viscosity on electrical conductivity was discussed by the Walden rule. The Bahe–Varela theory, derived from the the pseudo-lattice model, has been successfully applied to explain the influence of the mixture composition on electrical conductivity. Based on physicochemical characterization supported with computational simulations for binary mixtures (bmpyrrNTf2 + DEC), the interactions between these components were discussed.
•Densities of bmimNTf2 mixtures with propylene carbonate were measured.•Excess properties were calculated.•Formation of hydrogen bonds between IL and PC was discussed.•Electrical conductivity and ...viscosity were also measured.•Influence of temperature and composition on mixture properties were studied.
Densities of binary liquid mixtures of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, bmimNTf2, with propylene carbonate (PC) were measured at temperatures from (293.15 to 323.15)K and at atmospheric pressure over the whole composition range. The electrical conductivity was measured in the range from (293.15 to 328.15)K. Also, viscosity of bmimNTf2+PC binary mixtures was measured from (298.15 to 333.15)K. Excess molar volumes, VE, have been obtained from the experimental densities and were fitted to Redlich–Kister polynomial equation. Other volumetric properties, such as isobaric thermal expansion coefficients, partial molar volumes, apparent molar volumes and partial molar volumes at infinite dilution have been also calculated, in order to obtain information about interactions between PC and selected ionic liquid. Results are discussed in order to understand the hydrogen bonds formation between components of the mixture.
One of the new synthetic cathinones that has a high tendency to replace ecstasy and other established synthetic drugs is
N-
ethylpentylone, (NEP), due to its high potency, stimulative, hedonic and ...hallucinatory effects. In order to examine the interactions of
N
-ethylpentylone, the apparent molar quantities, thermal expansion coefficient and the apparent molar volume at infinite dilution were calculated from the experimental measurements of the density of NEP aqueous solutions in different temperature and molality ranges, from
T
= (293.15 to 313.15) K and from
m
= (0.0590 to 0.0977) mol·kg
−1
, respectively. The taste of
N
-ethylpentylone was estimated by calculated values of apparent specific molar volume at infinite dilution and it was concluded that its taste in aqueous solutions is bitter. Also, using the spectrofluorimetric technique, an intermolecular deactivation of in situ formed ethidium bromide (EB) complex with DNA (EB-DNA) was investigated in the presence of
N
-ethylpentylone. Obtained results indicated good affinity and efficiency of NEP to substitute EB from the EB-DNA complex via intercalation mode. Using molecular docking, it was concluded that the binding energy obtained for NEP indicates its higher affinity to interact with DNA, compared to methamphetamine and amphetamine, but lower compared to ecstasy. The affinity of NEP to bind to bovine serum albumin (BSA) was also investigated and discussed. It is shown that
N
-ethylpentylone could be efficiently transported and distributed through the blood and cells.
In this work structuring of water and insight into intermolecular interactions between water and fullerenol are studied throughout the process of forming nanoagglomerates at different temperatures ...applying both experimental and computational approaches. The obtained fullerenol nanoparticles (FNPs) are firstly characterized using dynamic light scattering, atomic force microscopy and transmission electron microscopy. The density, electrical conductivity and dynamic viscosity of aqueous fullerenol solutions are measured in the temperature range of 293.15 to 315.15 K. From the experimental density results other important thermodynamic values, such as apparent molar volumes and the partial molar volumes of water and fullerenol, are also calculated. To support the conclusion derived from the experimental density and calculated volumetric parameters, and to better understand the nature of the interactions with water, molecular dynamics simulations and radial distribution functions are also employed.
The possibility to prevent nutrition-related diseases that include scavenge of free radicals and to block chain reactions is very important and significant for human well-being. The aim of this study ...was to analyse different basil extracts, determine the relationship between total phenolic/flavonoid content and antioxidant activity in order to optimize its application in industry. The extraction involved different solvents (ethanol, methanol and water), extraction time (10 and 30 min and 24, 48 and 72 h), plant fragmentation level (0.3 and 2 mm) and the presence or absence of light. Antioxidant activity was investigated by applying spectrophotometric method and measuring the total phenolic and flavonoid content and DPPH radical scavenging activity. The content of total phenolics varied from 5.2 to 185.6 mg of gallic acid equivalents per gram of a dry extract and flavonoids ranged from 0.2 to 35.0 mg of quercetin per gram of a dry extract. All extracts presented a scavenging capacity and IC
50
values of DPPH radical inhibition ranged from 0.04 to 12.99 μg/ml. The evaluation of experimental data for eighty basil extracts was performed by chemometric analysis showing good correlation between yield and total phenolic compounds, as well as flavonoid content and inhibition of the DPPH radical.
Graphical abstract
In this work, the absorption spectra of cobalt(II) nitrate and chloride complexes in the composition
x
Ca(NO
3
)
2
–(1 –
x
)NH
4
NO
3
–H
2
O have been investigated in the 400–800 nm range of ...wavelength at
T
= 328.15 K and atmospheric pressure
p
= 101.3 kPa. Spectra were recorded in 0.3 Ca(NO
3
)
2
–0.7 NH
4
NO
3
–H
2
O solutions with variable water content (
R
= H
2
O/salt mole ratio;
R
ws
= 1.0, 1.2, 1.6 and 2.0), and in
x
Ca(NO
3
)
2
–(1 –
x
)NH
4
NO
3
–H
2
O (
x
= 0.3, 0.5 and 0.7) solutions where the H
2
O/salt mole ratio was kept constant (
R
ws
= 2.0). The blue shift of the absorption maximum with increasing water content (
R
ws
) suggests simultaneous coordination by water molecules and nitrate ions. From an analysis of the spectra, it can be concluded that the following complexes: Co(NO
3
)
4
(H
2
O)
2
2−
, Co(NO
3
)
2
Cl
2
2−
and CoCl
4
2−
were formed. The overall stability constants of these complexes and the corresponding resolved species spectra were calculated at
T
= 328.15 K.
In this work, four different oxygen functionalized ionic liquids, 1-(3-hydroxypropyl)-3-methylimidazolium chloride,OHC3mImCl, 1-(3-hydroxypropyl)-3-ethylimidazolium chloride OHC3eImCl, ...1-(2-oxobutyl)-3-methylimidazolium chloride, C2OC2mImCl and 1-(4-hydroxy-2-oxobutyl)-3-methylimidazolium chloride, OHC2OC2mImCl were synthesized in liquid state at room temperature. Detailed physico-chemical characterisation (density, viscosity and conductivity) supported with computational simulations for pure ionic liquid and their aqueous solutions were performed. Based on these examinations, interactions in pure ionic liquids and interactions between water and synthesized ionic liquids were discussed.
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