Structural Elucidation and Release Enhancement of the Florfenicol/β-Cyclodextrin Inclusion Complex

Abstract

The limited aqueous solubility and dissolution rate of Florfenicol (FLO) constrain its therapeutic efficacy. In this study, we enhance these properties by forming an inclusion complex with β-cyclodextrin (β-CD). Employing a cooling-based solution method, the FLO/β-CD complex was synthesized, which was verified to have a stoichiometry of 1:2 through combined nuclear magnetic resonance proton spectra and single-crystal structural analysis. A ternary phase diagram guided our development of a green synthesis route for the pure complex, leveraging slow solvent evaporation and cooling techniques. Significantly, we demonstrate that at temperatures of 10, 25, and 35 °C, the complex markedly improves FLO's solubility and dissolution rate. This work not only offers a valuable strategy to overcome the challenges associated with FLO's bioavailability but also provides insightful guidance for the industrial-scale production of high-purity FLO/β-CD complexes, presenting an advancement in the formulation of poorly soluble pharmaceutical compounds.