Study on the interactions of drug isoniazid in aqueous-D-xylose/L-arabinose solutions at different temperatures using volumetric, acoustic and viscometric approaches

Abstract

Volumetric, acoustic and viscometric properties of drug isoniazid in water and aqueous solutions of carbohydrates, D-xylose and L-arabinose (5% and 10% D-xylose/L-arabinose in water, w/w) were studied at various temperatures, T = (293.15–318.15) K and at atmospheric temperature. The apparent molar volumes, Vϕ and apparent molar compressibilities, Ks,ϕ were calculated from the experimentally measured densities and ultrasonic speeds. Limiting apparent molar volumes, Vϕ°, limiting apparent molar compressibilities, Ks,ϕ°, limiting molar expansibilities, Eϕ° and their corresponding transfer volumes, Vϕ,tr° and transfer compressibilities, Ks,ϕ,tr° of drug isoniazid from water to aqueous carbohydrate solutions were also evaluated. Falkenhagen Coefficients, A, Jones-Dole coefficients, B, variation of B with temperature, dB/dT, free energies of activation of viscous flow per mole of solvent, Δμ1°# and per mole of solute, Δμ2°#, enthalpies, ΔH°# and entropies, ΔS°# of activation of viscous flow were calculated from the viscosity measurements. The negative sign of dB/dT indicated the structure making ability of the drug isoniazid. The results obtained have been discussed in terms of solute-solvent interactions in order to understand the solvation behaviour of isoniazid in these aqueous-carbohydrate solutions.