DQAsomes:: A novel potential drug and gene delivery system made from Dequalinium™

Purpose. Dequalinium, a drug known for over 30 years, is a dicationic amphiphile compound resembling bolaform electrolytes. The purpose of our work was to determine the state of aggregation of dequalinium in aqueous medium and to investigate both, its ability to bind DNA and its potential to serve as a novel non-viral transfection vector. Methods. The form of aggregation was determined employing electron microscopic techniques. The DNA binding capacity of dequalinium was assayed using SYBR(TM) Green I stain. For in vitro cell transfection experiments plasmid DNA encoding for firefly luciferase was used. Results, Dequalinium forms in aqueous medium liposome-like aggregates, which we term DQAsomes. These dequalinium vesicles bind DNA and they are able to transfect cells in vitro with an efficiency comparable to Lipofectin(TM). Conclusions. Based on the intrinsic properties of dequalinium such as the in vivo selectivity for carcinoma cells and selective accumulation in mitochondria we propose DQAsomes as a novel and unique drug and gene delivery system.