Cholesterol-enriched erythrocyte-derived optical nanoparticles for NIR fluorescence imaging of intraperitoneal ovarian tumors in mice

We have engineered nanoparticles from erythrocytes doped with the near infrared (NIR) dye, indocyanine green. These particles can be functionalized with various biomolecules such as folate for targeted imaging of cancer cells. Externalization of phosphatidylserine from the inner to the outer leaflet of erythrocyte-derived particles is a common problem during the fabrication process, serving as a signal for phagocytic removal of the particles and reducing tumor targeting. Herein, we demonstrate the effectiveness of membrane cholesterol-enrichment and folate functionalization as a method to increase the efficacy of these particles for NIR fluorescence imaging of intraperitoneal ovarian tumors in mice.