Rapid Analysis of DOXIL Stability and Drug Release from DOXIL by HPLC Using a Glycidyl Methacrylate-Coated Monolithic Column

In recent years, nanomedicines have received growing attention in a range of medical applications, including selective drug delivery technology. In this context, the analysis of liposome stability and drug release from liposomes is of particular importance, as the efficacy of a nanomedicine is determined by the release of the encapsulated drug. We investigated the influence of the surrounding environment on the stability and release of the encapsulated drug (i.e., doxorubicin) from DOXIL. Thus, for the purpose of this study, we selected the liposomal anticancer drug, DOXIL, as a typical nanomedicine, and investigated the influence of the surrounding environment on release of doxorubicin from DOXIL. We found that two pathways existed for doxorubicin release, namely the collapse of DOXIL, and an increase in the permeability of the lipid bilayer. DOXIL collapse occurred upon the addition of high concentrations (>60%) of a methanol solution, while an increase in permeability occurred at temperatures above the phase transition temperature of the DOXIL lipid bilayer, under basic conditions, and in the presence of membrane-permeable bases (e.g., Tris). As DOXIL is particularly stable and limited collapse of DOXIL occurred under physiological conditions, it is expected that doxorubicin release within the body took place through permeability changes in the lipid bilayer of the DOXIL structure.