Solubility, Hansen Solubility Parameters and Thermodynamic Behavior of Emtricitabine in Various (Polyethylene Glycol-400 + Water) Mixtures: Computational Modeling and Thermodynamics

Abstract

This study was aimed to find out the solubility, thermodynamic behavior, Hansen solubility parameters and molecular interactions of an antiviral drug emtricitabine (ECT) in various “[polyethylene glycol-400 (PEG-400) + water]” mixtures. The solubility of ECT in mole fraction was determined at “T = 298.2 to 318.2 K” and “p = 0.1 MPa” using an isothermal method. The experimental solubilities of ECT in mole fraction were validated and correlated using various computational models which includes “Van’t Hoff, Apelblat, Yalkowsky-Roseman, Jouyban-Acree and Jouyban-Acree-Van’t Hoff models”. All the models performed well in terms of model correlation. The solubility of ECT was increased with the raise in temperature in all “PEG-400 + water” mixtures studied. The highest and lowest solubility values of ECT were found in pure PEG-400 (1.45 × 10−1) at “T = 318.2 K” and pure water (7.95 × 10−3) at “T = 298.2 K”, respectively. The quantitative values of activity coefficients indicated higher interactions at molecular level in ECT and PEG-400 combination compared with ECT and water combination. “Apparent thermodynamic analysis” showed an “endothermic and entropy-driven dissolution” of ECT in all “PEG-400 + water” combinations studied. The solvation nature of ECT was found an “enthalpy-driven” in each “PEG-400 + water” mixture studied.

Solubility Data, Solubility Parameters and Thermodynamic Behavior of an Antiviral Drug Emtricitabine in Different Pure Solvents: Molecular Understanding of Solubility and Dissolution

“…The DSC curves and various thermal parameters (i.e., T fus , ∆ H fus and ∆ C p ) of pure and equilibrated ECT were not varied significantly ( p > 0.05), suggesting that ECT exists in pure crystalline form which was not transformed into polymorphs/hydrates/solvates after solubility experiments [ 18 , 20 ]. In addition, the X-ray diffraction (XRD) patterns of pure and equilibrated ECT were also found to be similar in our previous publication [ 16 ]. Hence, the DSC spectra of present study and XRD patterns of our previous publication suggested no transformation of ECT into different forms.…”

“…The solubility of ECT in water at T = 298.2 K is reported elsewhere [ 2 ]. The mole fraction solubility values of ECT in water, PEG-400 and various (PEG-400 + water) mixtures at T = 298.2 K to 318.2 K and p = 0.1 MPa have also been reported in our previous article [ 16 ]. However, the quantitative solubility values of ECT in other investigated PS are not reported elsewhere.…”

“…The quantitative solubility value of ECT in water has been reported as 112 mg mL −1 at T = 298.2 K [ 2 ]. Recently, the solubility values of ECT in mole fraction in neat water, neat polyethylene glycol-400 (PEG-400) and various (PEG-400 + water) mixtures at T = 298.2 K to 318.2 K and p = 0.1 MPa have been reported in literature [ 16 ]. While, temperature-dependent solubilities and other physicochemical parameters of ECT in other studied solvents are not reported elsewhere.…”

Solubility Data of the Bioactive Compound Piperine in (Transcutol + Water) Mixtures: Computational Modeling, Hansen Solubility Parameters and Mixing Thermodynamic Parameters

“…Therefore, HSPs for PPN, pure THP, pure water and various “THP + water” mixtures free of PPN were computed in this research. The δ value for PPN, pure THP and pure water was computed by applying Equation (3) [ 49 , 51 , 52 ] as follows: in which “ δ = total HSP; δ d = dispersion HSP; δ p = polar HSP and δ h = hydrogen-bonded HSP”. The HSPs for PPN, pure THP and pure water were estimated using “HSPiP software (version 4.1.07, Louisville, KY, USA)” [ 51 ].…”

“…Therefore, HSPs for PPN, pure THP, pure water and various "THP + water" mixtures free of PPN were computed in this research. The δ value for PPN, pure THP and pure water was computed by applying Equation (3) [49,51,52] as follows:…”