Apparent Molar Compressibility Research Articles

Bio-inspired preparation of Ag NPs, rGO, and Ag/rGO nanocomposites for acoustical, antioxidant, and plant growth regulatory studies

Acoustical properties are essential for understanding the molecular interactions in fluids, as they influence the physicochemical behavior of liquids and determine their suitability for diverse applications. This study investigated the acoustical parameters of silver nanoparticles (Ag NPs), reduced graphene oxide (rGO), and Ag/rGO nanocomposite nanofluids at varying concentrations. Ag NPs and Ag/rGO nanocomposites were synthesized via a Bos taurus indicus (BTI) metabolic waste-assisted method and characterized using advanced techniques, including XRD, TEM, Raman, DLS, zeta potential, and XPS. The synthesized nanocomposites were evaluated for their acoustical, antioxidant, and plant growth-regulatory properties. Acoustical analysis revealed a linear relationship between the nanofluid concentration and density, with key parameters such as adiabatic compressibility, apparent molar compressibility, and apparent molar volume increase at lower concentrations. Irregular changes in ultrasonic velocity and other parameters at 0.025 mol/dm3 suggest unique nanoparticle-solvent interactions. The Ag/rGO nanocomposites exhibited superior antioxidative potential compared to Ag NPs, with DPPH scavenging activity reaching 65.69% and ABTS scavenging activity reaching 65.01% at 100 µg/mL. Plant growth studies have demonstrated enhanced germination rates (100% in spinach and 40% in fenugreek) and improved root and shoot elongation at 0.0025–0.005 mol/dm3. This study bridges the gap in understanding the acoustical and multifunctional properties of nanocomposites for biomedical, agricultural, and environmental applications.

Physico-chemical Study of Surface Active Ionic Liquid (SAIL) in Aqueous Inulin Solutions: Density and Speed of Sound Measurements

Colloidal formulations of surface active ionic liquid (SAIL) have substantial benefit as efficient carrier mainly for therapeutic/pharmaceutical agents. In this regard, density (ρ) and speed of sound (u) have been employed to evaluate the diverse interactions/association behaviour of greener SAIL tetrabutylammonium dodecylsulphate (TBADS) (0.222 to 2.2 mmol kg-1) in aqueous inulin solutions (0.0, 0.2 and 0.3% w/w) at five different temperatures ranging from 293.15 K to 313.15 K. The volumetric and acoustic parameters viz. isentropic compressibility (κs), apparent molar volume (Vφ) and compressibility (κs,φ), intermolecular free length (Lf), relative association (RA), specific acoustic impedance (Z) and molar sound number ([U]) have been calculated by using density (ρ) and speed of sound (u) values. The existence of hydrophilic/hydrophobic interactions for TBADS in aqueous inulin solution is suggested by the variations in volumetric parameters, which further supported by various calculated acoustic parameters. Thus, the interactional outcomes can offer implications that stabilized inulin in the presence of SAILs and can be utilized for the optimal biotic actions.

Insights from volumetric, acoustic, conductance and spectroscopic studies to study the molecular interactions of drug Levocetirizine in aqueous and aqueous glucose solutions at varying temperatures

Levocetirizine, an antihistamine, has been analyzed in relation to temperature by volumetric, acoustic, and spectroscopic methods to investigate its interaction with glucose, the predominant carbohydrate. Density and ultrasonic velocity for LC (0–0.10 mol dm−3) at different temperature (298.15, 308.15 and 318.15 K) in water and in aqueous solution of glucose (0.05, 0.10 and 0.15 mol kg−1) have been recorded using Anton Paar DSA 5000 M. The apparent molar volume (Vϕ), limiting apparent molar volume (Vϕ0), apparent molar compressibility (Kϕ,S), limiting apparent molar compressibility (Kϕ,S0) were computed utilizing the experimental data. In addition, the transfer parameters of LC from water to aqueous glucose solutions were identified and elucidated using the co-sphere model. The transfer volumes have been utilized to estimate the interaction coefficients. Limiting apparent molar expansibility (ϕE0) and Hepler’s constant was obtained to throw light upon the structure-making or structure-breaking effect of solute. Multiple acoustical parameters like isentropic compressibility (KS), relaxation strength (r), intermolecular free length (Lf), specific acoustic impedance (Z), Wada’s constant (W), relative association (RA), Rao’s constant (Rm), molar volume (Vm), Van der Waals constant (b), and free volume (Vf) were determined to validate the thermodynamic results.

Molecular interactional study of SDS and CTAB in aqueous medium of anti-HIV drugs (Emtricitabine and Lamivudine) at different temperatures: A physicochemical investigation

The present study deals with the interactions of Emtricitabine and Lamivudine (anti-HIV drugs) with anionic surfactant sodium dodecylsulphate (SDS) and cationic surfactant cetyltrimethylammonium bromide (CTAB) at (298.15–313.15) K temperature range by volumetry, compressibility and viscometric approach. The experimental values of sound velocity and density are used to compute various parameters such as apparent molar volume (φv), isentropic compressibility (κs), and apparent molar adiabatic compression (φκ) by employing cosphere overlap model. Relative viscosity parameter (ηr) evaluated from viscosity data also helps to understand various interactions prevalent in surfactant-drug-water ternary system. This attempt of extracting information about various physicochemical interactions of anti-HIV drugs with surfactants can prove beneficial to develop novel anti-HIV agents with better viral resistance activity.

Volumetric, compressibility and viscometric studies on intermolecular interactions of NaC and NaDC with Emtricitabine and Lamivudine in aqueous medium at (298.15–313.15) K

Bile salts are bio-compatible natural amphiphiles having a significant role in pharmaceutical field as a solubility and permeability enhancer and possess a great biological importance for release and transport of nutrients due to dynamic micellization behavior. Hence, to unfold the interactional mystery of drug − bile salt system in the field of anti-retroviral drugs, we have aimed to investigate solute–solute and solute–solvent interactions of bile salts (NaC and NaDC) with anti-HIV drugs (Emtricitabine and Lamivudine) by using various techniques like volumetry, compressibility, and viscometry at temperature range (298.15 K-313.15 K) with a regular variation of 5 K. Experimental density and speed of sound data have been used to evaluate various physicochemical parameters such as apparent molar volume (φv), isentropic compressibility (κs), and apparent molar adiabatic compression (φκ). The CMC values of bile salts in pure water and aqueous solution of ECT and LMV at 298.15 K have also been evaluated from speed of sound data which corroborate well with our earlier conductivity study on these surfactants. The trends of φv, κs and φκ values for both NaC and NaDC with temperature and in presence of drugs (ECT/LMV) indicate strong solute–solvent interactions in studied system. The results are elucidated in terms of electrostatic and hydrophilic-hydrophobic interactions in bile salt-drug-water system which is confirmed by co-sphere overlap model. Comparatively, NaC offers strong interactions with both drugs due to more hydrophilic character than NaDC. Similarly, out of ECT and LMV, ECT shows strong solute–solvent interactions with both bile salts due to more hydrophilic character than LMV. Relative viscosity parameter (ηr) determined from viscosity measurements further supports above results. This interactional knowledge of bile salts with ECT and LMV would be beneficial to develop a better mechanism in pharmacy for enhancing efficacy and permeability of anti-HIV drugs by using bile salts as a drug delivery agent.

A volumetric, ultraacoustical study and computational study of molecular interactions in 4-aminoantipyrine-aqueous-β-cyclodextrin solutions

Present work reports experimental densities and corresponding apparent and standard partial molar volumes, ultrasonic velocities and isentropic, apparent and standard partial molar compressibilities of 4-Aminoantipyrine-aqueous-β-cyclodextrin (0.000 mol∙kg−1, 0.001 mol∙kg−1, 0.005 mol∙kg−1, 0.010 mol∙kg−1and 0.015 mol∙kg−1) solutions at different temperatures. Transfer properties like transfer volumes and compressions were calculated. The refractive indices of these systems were also measured. The computational properties such as solvation energy (ΔESol), relative stabilization energy (ΔERel), complexation energy (ΔEComp) and change in volume (ΔV) were computed using DFT. The results from volumetric and acoustical studies have been evaluated in terms of molecular interactions and their existence confirmed from experimental and computational studies. The values of transfer volumes and compressibilities indicate the hydrophilic-hydrophilic interactions between polar groups of 4-Aminoantipyrine and hydroxyl groups of β-cyclodextrin dominating over hydrophobic-hydrophobic interactions between the phenyl group of 4-Aminoantipyrine and hydrophobic interior of β-cyclodextrin.

Isothermal compressibility, internal pressure studies of aqueous rare earth nitrate solutions at 298.15 K: An attempt to estimate ionic radii and understand inner– and outer–sphere exchange water structural interactions

In this communication, we report our analysis and results concerning the determination of ionic radii in aqueous solution phase for Lanthanum (La+3), Neodymium (Nd+3), Erbium (Er+3) and Ytterbium (Yb+3) ions in presence of nitrate (NO3-) anion at 298.15 K. The literature data for density, adiabatic compressibility, and specific heat capacity of solutions at constant pressure have been used to compute isothermal compressibility, internal pressure of solutions in limiting concentration range. The apparent molar isothermal compressibility of electrolytes and hydration numbers have been obtained. The electrostriction for rare earth cations and intrinsic volumes have been calculated using thermodynamic equations. The ionic radii of cations have been obtained using the ionic partial molar volume data of NO3- ions and the results are compared with those obtained for rare earth chlorides. The two series affect is also observed for ionic radii and internal pressure. The results have been explained on the basis of water structural effects due to electrostatic field and water dipole interaction between the inner– and outer–sphere water exchange reaction.

Volumetric-acoustic investigations of antihypertensive drug in aqueous acetaminophen system

Captopril is an antihypertensive drug used to lower the blood pressure in living organisms. In order to arbitrate and understand the synergy between antihypertensive drug viz., captopril and antipyretic drug acetaminophen in aqueous system, the density and sound velocity at different temperatures (293.15 to 318.15) K with temperature interval of 5 K were measured using Anton Paar density sound velocity meter (DSA5000M). The experimental measured data were further used to calculate volumetric and acoustic parameters such as apparent and partial molar volume, apparent and partial molar isentropic compressibility, partial molar expansibility, Hepler’s constant, compressibility hydration number, and intermolecular free length. Positive values of apparent molar volume (ϕv) and negative values of apparent and partial molar compressibility (ϕk and ϕko) of captopril in water and aqueous acetaminophen solution has been shown strong intermolecular interactions in solutions. Negative values of Hepler's constant indicate the structure breaking behavior of drug in water.

Review of Density and Ultrasonic Velocity of Various Complexes and Its Applications

This review paper delves into the fundamental principles, measurement techniques, and diverse applications of ultrasonic velocity and density. Ultrasonic velocity serves as a crucial parameter in various fields such as materials science, acoustics, and medical diagnostics whereas density is used for identifying substances, quality control, analyzing mixtures, assessing purity, explaining buoyancy, determining concentrations, calibrating instruments, monitoring pollution, and understanding reactivity. This paper provides an in-depth exploration of the underlying concepts, different measurement methods, and the wide-ranging applications of ultrasonic velocity and density. The ultrasonic velocity and density data have also been used to evaluate various acoustic parameters such as isentropic compressibility, apparent isentropic molar compressibility, solvation number of the solute and relative association. Ultrasonic velocity measurements are found to be useful for on-line assessment of the extent of degradation of mechanical properties associated with precipitation of intermetallics. Keywords: Density, Ultrasonic velocityThis review paper delves into the fundamental principles, measurement techniques, and diverse applications of ultrasonic velocity and density. Ultrasonic velocity serves as a crucial parameter in various fields such as materials science, acoustics, and medical diagnostics whereas density is used for identifying substances, quality control, analyzing mixtures, assessing purity, explaining buoyancy, determining concentrations, calibrating instruments, monitoring pollution, and understanding reactivity. This paper provides an in-depth exploration of the underlying concepts, different measurement methods, and the wide-ranging applications of ultrasonic velocity and density. The ultrasonic velocity and density data have also been used to evaluate various acoustic parameters such as isentropic compressibility, apparent isentropic molar compressibility, solvation number of the solute and relative association. Ultrasonic velocity measurements are found to be useful for on-line assessment of the extent of degradation of mechanical properties associated with precipitation of intermetallics. Keywords: Density, Ultrasonic velocity

Solute–solvent interactions of glycine, L–alanine, and L–valine in aqueous 1–butyl–3–methylimidazolium methylsulfate ionic liquid solutions at different temperatures

The intermolecular interactions of amino acids (glycine, L–alanine, and L–valine) in aqueous solutions of an ionic liquid, 1–butyl–3–methylimidazolium methylsulfate [Bmim][MeSO4] as a function of temperature have been investigated by combination of volumetric and acoustic methods. The density, ρ, and speed of sound, u, of glycine, L–alanine and L–valine in aqueous 1–buytl–3–methylimidazolium methylsulfate solutions have been measured in the temperature interval T = (288.15, 298.15, and 308.15) K and atmospheric pressure. These data have been used to calculate apparent molar volume (V∅), and apparent molar adiabatic compressibility (K∅,s) of these mixtures at different temperatures. Later, the standard partial molar volume (V∅0), standard partial molar volumes of transfer (ΔV∅0), standard partial molar adiabatic compressibility (K∅,s0), and standard partial molar adiabatic compressibility (ΔK∅,s0) of transfer have been determined for these amino acid solutions from density and speed of sound data. Also, hydration number (nH) and various group contribution have been calculated. Finally the results have been interpreted in terms of solute - solvent interactions that exist among the currently investigated systems.

Influence of temperature and anion type on thermophysical properties of aqueous solutions of morpholine based amino acid ionic liquids

Densities and sound velocities of aqueous solutions of N-butyl-N-methylmorpholine based amino acid ionic liquids (AAILs), including N-acetyl-L-alanine, N-acetyl-L-valinate, N-acetyl-L-leucinate, and N-acetyl-L-izoleucinate anions were measured at a temperature from 293.15 to 313.15 K at 5 K intervals and atmospheric pressure. These data were used to calculate the apparent molar volumes and the apparent molar compressibilities in the concentration range of (0.02 to 0.3) mol.kg−1. Infinite dilution values for the volumetric and acoustic properties were evaluated by an extrapolation procedure based on Redlich – Meyer type equations. The limiting apparent molar expansibility coefficients were also obtained from the slopes of the apparent molar volume at infinite dilution versus temperature. Using the Passynski method, the hydration numbers for AAILs in an aqueous medium were calculated. The results indicate that in the studied solutions, the ion–solvent interactions are determined by the hydrophobic effect, which results in the decrease of the limiting apparent molar compressibilities and an increase of limiting apparent molar expansibility coefficients in the order: [Mor1,4][N-Ac-L-Ala], [Mor1,4][N-Ac-L-Val], [Mor1,4][N-Ac-L-Leu], [Mor1,4][N-Ac-L-Izoleu]. The empirical slopes in Redlich –Rosenfeld – Meyer equations show that the hydrophobicity of amino acid anions is also responsible for the ion-ion interactions.

Apparent molar volume, compressibility, and spectroscopic studies of ionic surfactants in aqueous solutions of antibiotic gemifloxacin

This work aims to explore the interactions between a wide-spectrum bactericidal drug, gemifloxacin (GMF), and micelles of cationic (dodecyltrimethylammonium bromide, DTAB) and anionic (sodium dodecyl sulfate, SDS) surfactants at the molecular level under physiological conditions (using a phosphate buffer, pH 7.4). Various physical parameters are calculated from volumetric and acoustic data. These include apparent molar volume ( ɸ V ), apparent molar isentropic compressibility ( ɸ K ), isentropic compressibility ( K s ), specific acoustic impedance (Z), relative association (RA), intermolecular free length (Lf ) and sound velocity number (U). The obtained quantities are interpreted regarding of solute-solute and solute-solvent interactions employing the cosphere overlap model and electrostriction effect. Further, normal and differential UV-visible spectroscopy is employed to predict GMF locus in ionic micelles and to find the binding constant (Kb ) and partition coefficient (Kc ) along with the corresponding free energy changes of GMF-ionic micelle systems. The results demonstrate that the binding and partitioning of GMF with SDS is more significant than DTAB.

Expliciting the interactions of tramadol hydrochloride + choline chloride-based deep eutectic solvent + water systems: Thermodynamic aspects

In recent years, a new class of environmentally friendly solvents called deep eutectic solvents (DESs) have been employed in a number of operations in both academia and industry. The study described herein offers an assessment of a green solvent in the preparation of Drug delivery systems (DDSs) as well as delivery vehicles made of a deep eutectic system (DES) constituted of Choline Chloride (ChCl) and Urea (U). For the designing of such processes, there is a need for an understanding of the molecular interaction of Tramadol hydrochloride with DES. In this regard, we have experimentally measured density and sound velocity for Tramadol hydrochloride in aqueous solutions and in different concentrations of aqueous DES (i.e., 0.25, 0.50, and 1.0)mol.kg−1 within the concentration range 0 to 0.15 mol.kg−1 at various temperatures (288.15, 298.15, 308.15 and 318.15) K. In order to interpret the view on solute–solvent and solute–solute interactions, several derived parameters chiefly apparent molar volume of solute (Vϕ), isentropic compressibility (κS), apparent molar isentropic compressibility of solute (KS,ϕ) for tramadol hydrochloride in aqueous and in an aqueous DES solutions have been calculated from experimental density and speed of sound values. The limiting apparent molar volume of solute (Vϕ0) and limiting apparent molar isentropic compressibility of solute (KS,ϕ0) for binary as well as ternary systems have been calculated from apparent molar volume and compressibility values. The thermal coefficient of expansion (α) and partial molar isobaric expansion (Eϕ0) have been derived from the temperature dependence of limiting apparent molar volume of solute. Transfer volume (ΔVϕtrans0) and transfer compressibility ΔKS,ϕtrans0 of tramadol hydrochloride from aqueous to aqueous DES solutions have been calculated.

Investigations on molecular interactions of memantine hydrochloride in aqueous solutions by thermophysical methods and molecular dynamics simulations at different temperatures

The density (ρ), speed of sound (u), and refractive index (nD) of aqueous solutions of Memantine hydrochloride with molalities ranging from 0.0 to 0.05 at atmospheric pressure and temperatures between 305.15 and 320.15 K were investigated. The experimental results have been used to compute apparent molar volume (Vφ), limiting values of apparent molar volume (Vφ0), the limiting apparent molar expansibility (Eφ0), Hepler's constant (∂2Vφ0∂T2), apparent molar adiabatic compressibility (kφ), limiting values of apparent adiabatic compressibility (kφ0), specific refraction (RD), molar refraction (RM) and hydration number (nh). These data indicated the existence of substantial solute-solvent interactions in the liquid system, as well as hydrogen bond, dipole-dipole, dipole-induced-dipole interactions and solute structure-making capacity. Good correlations with the experimental studies were observed from molecular dynamics (MD) simulation studies.

STUDY OF MOLECULAR INTERACTIONS OF SUBSTITUTED 2-OXO-2-H-CHROMENE-3-CARBOHYDRAZIDE DERIVATIVES IN BINARY SOLVENTS USING ULTRASONIC INTERFEROMETER

At 32°C, the apparent molal volume (v), apparent molal compressibility (k), relative association (RA), and solvation number (Sn) of substituted 2-oxo-2-H-chromene-3-carbohydrazide derivatives in 60% DMF-water were measured. The data is used to determine the interaction that is taking place in the solution. The ultrasonic technique is used to determine the interaction of a solute and a solvent. The variation of factors in binary mixtures with different concentrations indicates a significant interaction between solute and solvent molecules, associative molecular interaction, and ion-solvent interaction.

THE BEHAVIOR OF BENZENE WITH PARABENS IN ISOPROPANOL BY USING ULTRASONIC AND VOLUMETRIC EXPERIMENTS

Benzene with Butyl/Pentyl Parabens is evaluated using the volumetric and acoustic study as a function of temperature. The properties such as partial and apparent molar volumeand partial and apparent molar compressibility of the mixtures were studied. The thermoacoustic properties of the mixture, such as acoustic impedanceand free lengthwere analyzed. These measurements were utilized to interpret the intermolecular interactions among the constituents.

Volumetric, Compressibility and Viscometric Approach to Study the Interactional Behaviour of Sodium Cholate and Sodium Deoxycholate in Aqueous Glycyl Glycine.

Viscosity, speed of sound (u), and density (ρ) have been measured in aqueous glycyl glycine solution over a temperature range from 293.15 to 313.15 K with a 5 K interlude to evaluate the volumetric and compressibility properties of bio-surfactants, namely sodium cholate (NaC; 1-20 mmol∙kg-1) and sodium deoxycholate (NaDC; 1-10 mmol∙kg-1). Density and viscosity findings provide information on both solute-solute and solute-solvent types of interactions. Many other metrics, such as apparent molar adiabatic compression (κS,φ), isentropic compressibility (κS), and apparent molar volume (Vφ), have been calculated from speed of sound and density measurements, utilising experimental data. The results show that the zwitterionic end group in the glycyl glycine strongly interacts with NaDC and NaC, promoting its micellization. Since the addition of glycyl glycine causes the bio-surfactant molecules to lose their hydrophobic hydration, the observed concentration-dependent changes in apparent molar volume and apparent molar adiabatic compression are likely attributable to changes in water-water interactions. Viscous relaxation time (τ) increases significantly with a rise in bio-surfactant concentration and decreases with increasing temperature, which may be because of structural relaxation processes resulting from molecular rearrangement. All of the estimated parameters have been analysed for their trends with regard to the different patterns of intermolecular interaction present in an aqueous glycyl glycine solution and bio-surfactant system.

Effect of choline lactate ionic liquid as entrainer on the thermodynamic properties of alcohols + water azeotropic mixtures

Ionic liquids could be used as entrainer in the azeotropic mixture separation process efficiently. Accordingly, the thermodynamic properties of ionic liquid choline lactate ([Ch][Lac]) as a potential entrainer have been studied in different azeotropic mixtures. In this respect, the density and speed of sound for binary systems containing (water + [Ch][Lac]) (ethanol/ 1-propanol/ 2-propanol) + [Ch][Lac])] and also ternary systems with different mass percent from alcohol-containing (water + alcohol + [Ch][Lac]) have been measured under a pressure 871 hPa at different temperatures T = (288.15 to 318.15) K. These data are used to calculate standard partial molar volume (Vφ0), and the limiting apparent molar compressibility (κφ0) using the Redlich-Mayer model besides the intermolecular free length (Lf) and relative association (RA) to interpret the existing interaction in the azeotropic mixture of the studied alcohols. Also, the scaled particle theory is used as a microscopic approach. All of the properties have been analyzed to interpret the interactions between the components of the mixture and 2-propanol has stronger interactions with the [Ch][Lac] in the azeotrope composition. The results suggest that the [Ch][Lac] could be used as an entrainer to separate 2-propanol more efficiently rather than the other studied alcohols.

Ultrasonic Studies of Substituted Aryl Bisthiourea in Binary Solution at 298K Temperature

The ultrasonic velocity (u), density (ρ) and viscosity (η) have been measured for substituted aryl Bisthiourea in binary solution at 298K temperature by using ultrasonic interferometric technique. The observed experimental data have been used to study molecular interactions in different percent composition of 1,4 dioxane and water binary solution for different parameters such as adiabatic compressibility, apparent molar volume, apparent molar compressibility, relative association, acoustic impedance , free length, and relaxation time.

Influence of temperature and concentration on the molecular interactions of pyrrolidinium-based ionic liquid with water and alcohols: An experimental and DFT studies

The purpose of the present work is to explore the influence of concentration and temperature on solute–solvent interactions of binary mixtures of ionic liquid (IL) 1-methyl-1-propyl pyrrolidinium tetrafluoroborate ([MPpyr][BF 4 ]) and water, alcohols (methanol and ethanol) at 298.15, 303.15, 308.15 and 313.15 K under atmospheric pressure. The thermophysical properties such as the apparent molar volume ( V ϕ ), apparent molar adiabatic compressibility ( κ ϕ ), and limiting apparent molar volumes ( V ϕ 0 ), limiting apparent molar adiabatic compressibility ( κ ϕ 0 ), the limiting apparent molar expansibility ( E ϕ 0 ), thermal expansion coefficients ( α P ) were evaluated from experimental density ( ρ ) and speed of sound ( u ) data using suitable Redlich–Mayer type equation. V ϕ 0 and ( κ ϕ 0 ) values explain that the IL-solvent interaction in water, are stronger than the those between either methanol or ethanol with IL. Density functional theory (DFT) results are performed using the B3LYP/6–31++G (d,p) method, shows that the prominent interactions within the IL which are aliphatic C–H···anion interactions while the prominent interactions between the IL and the selected solvents are O − H···anion solute–solvent interactions. More importantly, DFT results confirm the trends observed from experimental findings, that the interaction involving IL in water is stronger than those involving either methanol or ethanol solvent with IL.