Effect of temperature on solvation behaviour of diclofenac sodium salt in aqueous glycine and l-proline solutions

• Solvation behaviour of diclofenac drug studied in aqueous solutions.
• Density and speed of sound of drug in aq. glycine and l-proline are measured.
• Hydrophobic nature of diclofenac sodium salt is studied.
• Effect of temperature on solvation of diclofenac sodium salt is analysed.

Apparent molar volume (V2,ϕ) and apparent molar isentropic compressibility (Ks,2,ϕ) of diclofenac sodium salt (DSS) drug within the concentration range of (0.001 to 0.008) mol · kg−1 in (0.01, 0.03 and 0.05) mol · kg−1 aqueous glycine and l-proline solutions are computed from the experimental density (ρ) and speed of sound (u) values at T = (293.15 to 313.15) K and atmospheric pressure. Derived parameters such as partial molar properties, transfer partial molar properties, hydration numbers and Hepler’s constant are computed from the data of V2,ϕ and Ks,2,ϕ. These parameters have been used to understand the effect of temperature on interactions between DSS drug and aqueous glycine/l-proline solution. Furthermore, the structure making and breaking ability of DSS drug in probed solutions are analysed at experimental conditions.