Phase Behavior of Mixtures Containing Antibiotics. Chloramphenicol Partitioning

Abstract

Phase equilibrium behavior of antibiotics is important in drug design and for optimization of the recovery processes in manufacturing. Antibiotics are high-cost fine chemicals, mostly manufactured by fermentation using inexpensive substrates. The major cost of manufacturing is involved in the separation processes. The aqueous/organic partitioning behavior of a clinically important antibiotic, chloramphenicol, is measured. The organic phase includes the pure solvents n-hexane, chloroform, diethyl ether, and ethyl acetate. In addition, measurements are also made for a mixed organic phase composed of n-hexane + ethyl acetate. Partitioning increases with the hydrogen bonding tendency of the solvent in the order n-hexane < chloroform < diethyl ether < ethyl acetate. Based on UNIQUAC and lattice−fluid hydrogen-bonding theories, an activity coefficient model (UNIQUAC-HB) is developed that includes hydrogen-bonding interaction. Single-solvent organic-phase data are correlated with the model, and free energy of hydrogen bonding parameters are obtained. Predictions made for mixed-solvent organic-phase systems agree well with the experimental data without using any adjustable parameter.

Removal of phenol from aqueous solution by Mahua seed activated carbon: Kinetic, isotherm, mass transfer and isosteric heat of adsorption studies

“…values 5.25×10 -5 , 2.49×10 -5 and 1.61×10 -5 cm/s were obtained at temperature 308, 318 and 328 K, respectively, indicating that the transfer of phenol from bulk of the liquid to adsorbent surface is very rapid and the adsorbent is suitable for removal of phenol from aqueous solution. Similar findings related to determination of mass transfer coefficient for various adsorbate-adsorbent systems have been reported previously [36][37][38][39][40][41].…”

Solubility of Antibiotics in Different Solvents. 1. Hydrochloride Forms of Tetracycline, Moxifloxacin, and Ciprofloxacin

“…[9][10][11][12][13] Several authors have used empirical equations to correlate antibiotic solubilities. [14][15][16][17][18] Recently, group-contribution methods have been used to predict solubilities of larger organic compounds. 19,20 The development of new predictive models and the improvement of the classic models for the phase equilibrium behavior of complex multifunctional molecules such as antibiotics has been difficult to achieve, because of the lack of reliable experimental data.…”

Application of a free volume model in correlating thermodynamic properties of β-lactam, tetracycline, fluoroquinolone and chloramphenicol antibiotic groups in associating fluids

“…The experimental data for the partition coefficients of antibiotics in solvents were obtained from references (Gupta et al, 1997;Kumar et al, 1998a,b). Table 3 presents the regressed values of the parameters for the UNIQUAC and the UNIQUAC-NRF models and those for the proposed model.…”

“…Hamelink et al (2002) measured and modeled activity coefficient and solubility of antibiotics in aqueous electrolyte solutions. Gupta et al (1997) and Kumar et al (1998a,b) studied the equilibrium partitioning coefficient of antibiotics in different organic solvents. Also, Taboada et al (2000) and Barbosa et al (2003) studied surface behavior of aqueous antibiotic solutions.…”