Erythrocyte-Derived Optical Constructs for Targeted Fluorescence Imaging and Combined Chemo-Phototheranostics

Erythrocyte-derived delivery platforms have potential for personalized theranostics. Key advantages of using this platform include: improved biocompatibility based on fabrication of the constructs from autologously-derived blood, extended in vivo circulation time, tunable size (ranging from nano- to micron-size scale) to provide capability for various clinical applications ranging from tumor to vascular imaging, encapsulation of various payloads (fluorescent probe and/or chemotherapeutic drug), and surface modification for targeted specific biomarkers. In particular, erythrocyte-derived nanoparticles can be doped with near infrared (NIR) chromophores, such as FDA-approved indocyanine green (ICG) and functionalized with antibodies to provide dual capabilities for targeted near-infrared imaging and phototherapy. We demonstrate the synthesis and characterization of these structures, as well as, their capability for in vitro targeting of cancer cells. Furthermore, we studied the effects of particle size on biodistribution and toxicological evaluation of erythrocyte-derived constructs in healthy mice. In addition, these erythrocyte-derived platforms can be customized for light-triggered combined chemotherapy and phototherapy by co-loading doxorubicin (DOX) and ICG