Volume-related interaction properties of the pharmaceutical mebicar (N-tetramethylglycoluril) in aqueous sucrose solutions between (278.15 and 318.15) K and at ambient pressure

Densities for solutions of the pharmaceutical mebicar (N-tetramethyl-substituted glycoluril) in aqueous sucrose were measured using a hermetically sealed vibrating U-tube densimeter, with an uncertainty of ∼0.03 kg m−3, at T = (278.15, 288.15, 298.15, 308.15, and 318.15) K and p = (99.6 ± 0.8) kPa. The solution molality was ranged from (0.0545 to 0.207) mol kg−1 for the aqueous sucrose (Suc) and from ca. (0.1 to 0.4) mol kg−1 for the mebicar (Meb) dissolved in it. The density data were used to calculate the apparent molar volumes and expansibilities (down to infinite dilution) for Meb as a solute, as well as Meb – Meb and Meb – Suc pairwise interaction coefficients over the whole temperature range under study. The results were discussed in terms of volume-related interaction effects occurring in the ternary liquid system being formed. It was concluded that the hydrophilic constituent (via H-bonding) are predominant in the solute – co-solute interactions and Suc has an overall stabilizing influence on the process of Meb hydration. © 2025 Elsevier B.V.