Densities and Speeds of Sound of Antibiotic Drug Chloramphenicol with <scp>l</scp>-Leucine and Glycyl-<scp>l</scp>-leucine in Aqueous Medium at <i>T</i> = (288.15–318.15) K: A Volumetric, Ultrasonic, and UV Absorption Study

Abstract

From the density (ρ) and speed of sound (c) measurements, the interactions of drug chloramphenicol with l-leucine and the dipeptide glycyl-l-leucine, have been examined in aqueous medium at T = (288.15–318.15) K and experimental pressure p = 0.1 MPa. For l-leucine and the dipeptide, the apparent molar volume (Vϕ), the apparent partial molar volume (Vϕo), and the apparent partial molar volumes of transfer (ΔVϕo), from water to aqueous chloramphenicol have been calculated from density data. We have also calculated the limiting apparent molar expansibilities. From the speed of sound data, apparent molar isentropic compression (Kϕ,s), apparent partial molar isentropic compression (Kϕ,so), and apparent partial molar isentropic compression of transfer (ΔKϕ,so) have been calculated. The pair and triplet interaction coefficients are determined from apparent partial molar volumes of transfer and apparent partial molar isentropic compression of transfer. For the present mixtures, the absorption spectra have also been recorded with the help of UV–visible spectrophotometer. Through the perusal of these calculated parameters, a detailed insight into the physicochemical interactions, for example, ion–hydrophilic, hydrophilic–hydrophilic, and hydrophilic–hydrophobic interactions in the l-leucine/glycyl-l-leucine-drug system, along with the structure-making/structure-breaking tendency of the l-leucine and the dipeptide, have been obtained.