Measurement, Modeling, and Thermodynamic Evaluation of Sulbutiamine Solubility in 11 Monosolvents and One Binary Solvent Mixture from 278.15 to 318.15 K

Sulbutiamine (SBT) is a vitamin B1 derivative with multiple pharmacological activities. Low water solubility and the lack of systematic solubility studies have hindered the development of its formulations. In this study, the solubility of SBT at temperatures ranging from 278.15 to 318.15 K was measured in 11 monosolvents and one binary solvent (P = 0.1 MPa) by the static method. The findings indicated that SBT exhibited optimal solubility in acetone and isopropanol. And the cosolvency phenomenon was discovered in a binary solvent (acetone + water). It was demonstrated that the solubility of SBT increased in accordance with an increase in temperature. In addition, solubility is analyzed from a variety of perspectives, including hydrogen bonding, polarity, Hansen Solubility parameters and the KAT-LSER. The Apelblat model, the Van’t Hoff model, the Jouyban model, the Generalized Steady-State model (GSM model), the Sun model, and the Apelblat-Jouyban-Acree model were used to fit the solubility values. The disparities between the experimental and calculated values of solubility were determined by means of RMSD, ARD, and RD. Results demonstrated that all employed models achieved satisfactory correlation performance.