Exploring molecular interactions of sucrose in aqueous potassium clavulanate solutions at different temperatures: volumetric and acoustic approaches

Abstract

Density and acoustic measurements as a function of temperature and ambient pressure have been used to examine molecular interactions, structural variables, and hydration behaviour in the ternary (potassium clavulanate/sucrose + water) system. Numerous thermodynamic and acoustic parameters, such as apparent molar volume ($V_{2,\phi }$) and apparent molar isentropic compressibility (${\text{Ks}}_{2,\phi } )$; limiting apparent molar volume ($V_{2,\phi }^{\infty }$) and limiting apparent molar isentropic compression (${\text{Ks}}_{2,\phi }^{\infty }$); and limiting apparent molar volume of transfer ($\Delta^{{{\text{tr}}}} V_{2,\phi }^{\infty }$) and isentropic compression of transfer ($\Delta^{{{\text{tr}}}} {\text{Ks}}_{2,\phi }^{\infty }$), are derived from the experimentally measured density and speed of sound. Partial molar expansibility ($E_{\phi }^{0}$), its first-order derivative $\left( {\partial E_{\phi }^{0} /\partial T} \right)p$, pair-triplet interaction coefficients ($V_{{{\text{AB}}}}$, $K_{{{\text{AB}}}}$, $V_{{{\text{ABB}}}}$, $K_{{{\text{ABB}}}}$), hydration number ($n_{{\text{H}}}$), and some of the empirical parameters calculated. The cosphere overlap model is used to understand the values of $(\Delta^{{{\text{tr}}}} V_{2,\phi }^{\infty } )$ and $\left( {\Delta^{{{\text{tr}}}} {\text{Ks}}_{2,\phi }^{\infty } } \right)$. The positive values of $\left( {\partial E_{\phi }^{0} /\partial T} \right)p$ indicate the structure-making ability of sucrose in aqueous potassium clavulanate solution, while the partial molar properties suggest the formation of hydrogen bonds in the system. Taken together, these characteristics suggested that the investigated ternary combination possessed substantial solute–solvent interactions at the temperature and composition investigated.