Development of anti-HER2 fragment antibody conjugated to iron oxide nanoparticles for in vivo HER2-targeted photoacoustic tumor imaging

HER2 (epidermal growth factor receptor 2)-targeted tumor diagnosis provides biomedical information on tumor malignancy. By utilizing a photoacoustic (PA) imaging technique, which detect ultrasonic waves thermoelastically induced by the absorption of photons by PA contrast agent through PA effect, iron oxide nanoparticles (IONPs) (20 nm, 50 nm, or 100 nm) conjugated with anti-HER2 moieties (Herceptin, single chain Fv (scFv), or peptide) were evaluated for HER2-targeted photoacoustic tumor imaging (left panel). The 20-nm IONPs conjugated with scFv demonstrated high affinity and specific binding to HER2, and selectively visualized HER2-positive tumors in photoacoustic imaging studies (right panel).329