Doxorubicin-Sensitized Luminescence of NIR-Emitting Ytterbium Liposomes: Towards Direct Monitoring of Drug Release.

Drug-loaded liposomes are typical examples of nanomedicines. We show here that doxorubicin, the anti-cancer agent in the liposomal drug Doxil, can sensitize Ytterbium (Yb ) and generate its near-infrared (NIR) emission. When doxorubicin and amphiphilic Yb chelates are incorporated into liposomes, the sensitized emission of Yb is dependent on the integrity of the particles, which can be used to monitor drug release. We also established the first demonstration that the NIR Yb emission signal is observable in living mice following intratumoral injection of the Yb -doxorubicin-liposomes, using a commercial macroscopic setup equipped with a NIR camera.