Determination and Correlation of Solubility of Metformin Hydrochloride in Aqueous Binary Solvents from 283.15 to 323.15 K

Metformin hydrochloride (MET center dot HCl) is one of the most widely used oral hypoglycemic drugs in the world. In addition to hypoglycemic effects, MET center dot HCl also has anti-inflammatory, anti-tumor, anti-aging, and other effects, showing good efficacy and safety of single and combined treatment. The solubility of MET center dot HCl in water, water + N,N-dimethylformamide, water + acetonitrile, and water + n-propanol was measured by the gravimetric method under atmospheric pressure at temperatures ranging from 283.15 to 323.15 K. The solubility of MET center dot HCl has a positive correlation with temperature and water content. The experimental solubility data in binary solvents was correlated by the modified Apelblat model, CNIBS/R-K model, Apelblat-Jouyban-Acree model, and.h model. By comparing the average ARD % values of the four models, it is found that the modified Apelblat model (ARD % = 1.26) provides better correlation. Hansen solubility parameters and apparent thermodynamic parameters were calculated to analyze the solubility behavior, indicating that the dissolution process is endothermic and entropically favorable.

Automated summary

Metformin hydrochloride, a widely used oral hypoglycemic drug, has been found to have not only hypoglycemic effects but also anti-inflammatory, anti-tumor, and anti-aging effects. The solubility of Metformin hydrochloride was found to increase with temperature and water content, and the modified Apelblat model provided the best correlation to describe the solubility behavior.