Assessing the Solubility of Baricitinib and Drug Uptake in Different Tissues Using Absorption and Fluorescence Spectroscopies

The low water solubility of baricitinib (BCT) limits the development of new formulations for the topical delivery of the drug. The aims of this study were to assess the solubility of BCT in different solvents, including Transcutol, a biocompatible permeation enhancer that is miscible in water, to evaluate the drug uptake in human skin and porcine tissues (sclera, cornea, oral, sublingual, and vaginal), and to subsequently extract the drug from the tissues so as to determine the drug recovery using in vitro techniques. Analytical methods were developed and validated for the quantification of BCT in Transcutol using absorption and fluorescence spectroscopies, which are complementary to each other and permit the detection of the drug across a broad range of concentrations. Results show that Transcutol permits an increased drug solubility, and that BCT is able to penetrate the tissues studied. The solutions of BCT in Transcutol were stable for at least one week. Hence, Transcutol may be a suitable solvent for further development of topical formulations.

Thermodynamic properties of active pharmaceutical ingredients that are of interest in COVID-19

The pure component properties are estimated for active pharmaceutical ingredients that are related or proposed for the treatment of severe acute respiratory syndrome-CoronaVirus-2. These include Baricitinib, Camostat, Chloroquine, Dexamethasone, Hydroxychloroquine, Fingolimod, Favipiravir, Thalidomide, and Umifenovir. The estimations are based on group contribution⁺ (GC) models that contain combined group contribution and atom connectivity index with uncertainties in the estimated property values. The thermodynamic properties that are reported include boiling point, critical temperature, critical pressure, critical volume, melting point, standard Gibb's energy of formation, standard enthalpy of formation, enthalpy of fusion, enthalpy of vaporization at 298 K, enthalpy of vaporization at boiling point, entropy of vaporization at boiling point, flash point, Hildebrand solubility parameter, octanol/water partition coefficient, acentric factor, and liquid molar volume at 298 K. The reported properties are not available in the literature and thereby is an incremental development for reliable process engineering.

DFT study on the structural and chemical properties of Janus kinase inhibitor drug Baricitinib

Baricitinib is a small molecule used to treat moderate to severe rheumatoid arthritis (RA) in adults. It is an inhibitor of Janus kinase 1 and 2 (JAK1 and JAK2). It has also been repurposed as a potential treatment for Covid 19. The current study has been carried out to understand the structural and chemical properties of this molecule. The molecule is optimized by using density functional theory (DFT) method. The DFT calculations are performed using Gaussian 09 W software package. The bond lengths and bond angles between atoms in the molecules are investigated. The intramolecular interaction within the molecule is identified using the natural bond orbital (NBO) study. The atom in molecule (AIM) study is performed using Multiwfn software. All the calculations are performed at B3LYP /6311G++ (d, p) level of theory. The molecular parameters, such as first-order hyperpolarizability, HOMO-LUMO energy gap, global electrophilicity index, dipole moment, chemical potential, hardness, ionization energy and electron affinity are determined from the calculation. The molecular docking analysis of Baricitinib is also carried out against different target proteins such as 6VSB, 6W9C and 6LU7.

Solubilization, Hansen solubility parameters and apparent thermodynamic parameters of

The solubilization, Hansen solubility parameters (HSPs) and apparent thermodynamic parameters of a novel anticancer medicine osimertinib (OMT) in binary propylene glycol (P) + water (W) cosolvent mixtures were evaluated. The mole fraction solubility (x e) of OMT in various (P + W) cosolvent mixtures including neat P and neat W was determined at T = 298.2–318.2 K and p = 0.1 MPa by applying a saturation shake flask method. HSPs of OMT, neat P, neat W and (P + W) cosolvent compositions free of OMT were also estimated. The x e values of OMT were regressed with Van’t Hoff, modified Apelblat, Yalkowsky-Roseman, Jouyban-Acree and Jouyban-Acree-Van’t Hoff models with an average errors of <3.0 %. The highest and lowest x e value of OMT was estimated in neat P (2.70 × 10−3 at T = 318.2 K) and neat W (1.81 × 10−5 at T = 298.2 K), respectively. Moreover, HSP of OMT was found to be closed with that of neat P. The solubility of OMT was found to be increased significantly with an increase in temperature and P mass fraction in all (P + W) cosolvent compositions including neat P and neat W. The results of activity coefficients suggested higher molecular interactions in OMT-P combination compared with OMT-W combination. The results of thermodynamic studies indicated an endothermic and entropy-driven dissolution of OMT in all (P + W) cosolvent compositions including neat P and neat W.

Solubility determination, computational modeling, Hansen solubility parameters and apparent thermodynamic analysis of brigatinib in (ethanol + water) mixtures

The solubility and various thermodynamic parameters of an antitumor drug brigatinib (BRN) in various ethanol (EtOH) + water (H2O) mixtures were determined in this study. The mole fraction solubility (x e) of BRN in various (EtOH + H2O) mixtures including pure EtOH and pure H2O was obtained at T = 298.2–323.2 K and p = 0.1 MPa by adopting a saturation shake flask method. Hansen solubility parameters (HSPs) of BRN, pure EtOH, pure H2O and (EtOH + H2O) mixtures free of BRN were also computed. The x e values of BRN were correlated using Van’t Hoff, Apelblat, Yalkowsky–Roseman, Jouyban–Acree and Jouyban–Acree–Van’t Hoff models with mean errors of <2.0%. The maximum and minimum x e value of BRN was obtained in pure EtOH (1.43 × 10−2 at T = 323.2 K) and pure H2O (3.08 × 10−6 at T = 298.2 K), respectively. The HSP of BRN was also found more closed with that of pure EtOH. The x e value of BRN was obtained as increasing significantly with the rise in temperature and increase in EtOH mass fraction in all (EtOH + H2O) mixtures including pure EtOH and pure H2O. The data of apparent thermodynamic analysis showed an endothermic and entropy-driven dissolution of BRN in all (EtOH + H2O) mixtures including pure EtOH and pure H2O.

Solubility Data and Computational Modeling of Baricitinib in Various (DMSO + Water) Mixtures

The solubility and thermodynamic analysis of baricitinib (BNB) in various dimethyl sulfoxide (DMSO) + water mixtures were performed. The "mole fraction solubilities (xe)" of BNB in DMSO and water mixtures were determined at "T = 298.2-323.2 K" and "p = 0.1 MPa" using an isothermal saturation technique. "Hansen solubility parameters (HSPs)" of BNB, pure DMSO, pure water and "DMSO + water" mixtures free of BNB were also estimated. The xe data of BNB was regressed well by five different thermodynamics-based co-solvency models, which included "Apelblat, Van't Hoff, Yalkowsky-Roseman, Jouyban-Acree and Jouyban-Acree-Van't Hoff models" with overall deviations of <5.0%. The highest and lowest xe value of BNB was computed in pure DMSO (1.69 × 10-1 at T = 323.2 K) and pure water (2.23 × 10-5 at T = 298.2 K), respectively. The HSP of BNB was found to be closer to that of pure DMSO. Based on activity coefficient data, maximum solute-solvent molecular interactions were observed in BNB-DMSO compared to BNB-water. The results of "apparent thermodynamic analysis" indicated endothermic and entropy-drive dissolution of BNB in all "DMSO + water" combinations including mono-solvents (water and DMSO). "Enthalpy-entropy compensation analysis" showed enthalpy-driven to be the main mechanism of solvation of BNB.

Temperature Dependent Solubility of Benzoic Acid in Aqueous Phase and Aqueous Mixtures of Aliphatic Alcohols

The benzoic acid solubility in aqueous phase and in various aqueous mixtures of methanol, ethanol and 2-propanol was determined at temperatures ranging from 303 to 333 K by an analytical technique. The results showed that the solubility of the acid in alcohols-water binary mixtures is high as compared to pure aqueous phase. The addition of alcohols to water favors the dissolution of benzoic acid which increases further with the increase in alcohols content of water within the investigated temperature range. The benzoic acid solubility in water alone and aqueous mixtures of the selected alcohols was in the order of; 2-propanol in water > ethanol in water > methanol in water > pure water. It is also observed that within the investigated temperature range, the acid solubility increases with rise in temperature in both the aqueous phase and alcohols-water binary solvents. The logarithm of the mole fraction of the acid’s solubility also showed a linear trend against the temperature. The experimental results obtained in the current study were compared with the reported literature for the studied acid and other organic acids in various solvents and showing a good agreement. The study will have implications in the processes involving separation, crystallization and pharmaceutical formulation in various industries.