Studies on Volumetric and Sound Velocity of Ciprofloxacin in Aqueous Solution of Glucose, Sodium Chloride & Potassium Chloride Salts at Different Temperatures

Abstract

In this study, volumetric and sound velocity method was applied to analyze the interaction of ciprofloxacin on the structure of glucose, NaCl and KCl. Densities and sound velocities of glucose, NaCl and KCl in water and in aqueous ciprofloxacin (0.03, 0.045 and 0.06) mol.kg-1 solutions have been studied at 293.15 K to 318.15 K with an interval of 5 K temperature. The density values have been used to calculate apparent molar volume (φv), limiting apparent molar volume (φv 0), limiting apparent molar volume transfer (Δtrφv 0), apparent molar expansibilities (δφv 0/δT)p and Hepler constant (δ2φv 0/δT2)p. The acoustic properties such as adiabatic compressibility (βs), apparent molar adiabatic compressibility (φk), limiting apparent molar adiabatic compressibility (φk 0), apparent molar adiabatic compressibility of transfer (Δtrφk 0), acoustic impedance (Z), relative association (RA) and hydration number (nH) have also been calculated by densities and sound velocities data. The densities increase with the increase of concentration of glucose, NaCl and KCl. Densities of glucose, NaCl and KCl in aqueous ciprofloxacin solutions are higher than that of glucose, NaCl and KCl in aqueous solution. The increase of density with concentration of glucose, NaCl and KCl can be attributed to solute-solvent interaction. The limiting apparent molar volumes (φv 0) are positive at the studied temperatures for the all mixtures indicate the presence of solute-solvent interactions. The positive values of Sv indicate strong solute-solute interaction and φv 0 values suggest the dominance of solute-solvent interaction. The limiting apparent molar volume transfer (Δtrφv 0) values have been found negative for NaCl and KCl in (0.03 and 0.045) and (0.03, 0.045 and 0.06) mol.kg-1 aqueous ciprofloxacin solutions respectively, which suggest the existence of ion-hydrophobic and hydrophobichydrophobic group interaction. But Δtrφv 0 values are positive for glucose and NaCl in (0.03, 0.045 and 0.06) and 0.06 mol.kg-1 aqueous ciprofloxacin respectively, which suggest the existence of ion-hydrophilic and hydrophilic-hydrophilic interactions. The values of limiting apparent molar expansion (Eφ 0) are positive. The Hepler constant (δ2φv 0/δT2)p values are small negative for all studied glucose, NaCl and KCl suggest the studied systems act as structure makers. The values of partial molar volumes ( 2) increase with increasing concentration of glucose, NaCl and KCl for all studied systems. The sound velocity increases with the increase of concentration of glucose, NaCl and KCl. Sound velocities of glucose, NaCl and KCl in aqueous ciprofloxacin solutions are higher than those of glucose, NaCl and KCl in aqueous solution. This indicate that the increase of compactness of the medium with the increase in glucose, NaCl and KCl and ciprofloxacin concentration. The adiabatic compressibility (βs) decreases with the increasing concentration of glucose, NaCl and KCl. This indicates that water molecules around the glucose, NaCl and KCl are less compressible than the water molecules in the bulk solution. The negative apparent molar adiabatic compressibility (φk) values indicate the greater loss of structural compressibility of water. The values of limiting apparent molar adiabatic compressibility (φk 0) are negative. The values of apparent molar adiabatic compressibility transfer (Δtrφk 0) are mainly positive which suggest the existence of strong ion-solvent interaction. At lower concentration, negative values of Δtrφk 0 indicate that increase in hydrophobic-hydrophobic group interactions. The small Sk values also indicates the domination of solute-solvent interaction over solute-solute interaction. The acoustic impedance, Z increases with the increase of concentration of glucose, NaCl and KCl. The relative association, RA decreases linearly with increasing the concentration of solute indicates the increase of solute-solvent interaction. The positive hydration number (nH) values indicate an appreciable solvation of solutes.