Biophysical characterization, nanoscale composition and cell uptake studies of pH-sensitive drug delivery systems

Abstract

Nanocarrier-based chemotherapy is one of the few nanotechnology-based medical therapies that reached the clinics. This happened already in 1995, when the commercial anti cancer drug delivery system DOXIL® was introduced in the market [1]. Albeit these early developments, still today nanotechnology-based drug delivery systems are far from reaching optimal selectivity and controlled release ability. In our study we use different liposomal formulations designed for pH-sensitive drug release and study their biophysical characteristics, when used for trafficking paclitaxel (PTX) and doxorubicin (DOX), both widely used chemotherapeutic anti-cancer drugs. Our work describes a combined spectroscopy and imaging approach to evaluate the biophysical properties of liposomal formulations. We study the nanoscale composition of the nanocarriers using molecular rulers in a fluorescence quenching assay, and analyze the cell uptake characteristics based on the autofluorescence of DOX using confocal microscopy.