Long circulating near infrared fluorescent nanoparticles for diagnosis and photodynamic therapy of cutaneous cancers

Indocyanine green (ICG) is a near-infrared fluorescence contrast agent, which has enormous potential in early tumor diagnosis and therapy. The objective of this study is to develop biodegradable nanoparticles entrapping ICG and to characterize its intracellular uptake and photodynamic activity in different cancer cell lines. Nanoparticles entrapping ICG were engineered, characterized and the intracellular uptake of ICG was investigated in B16-F10 and C-33A cancer cell lines. The photodynamic activity of ICG-loaded nanoparticles was also investigated. The nanoparticles enhanced the intracellular uptake of ICG and showed significant photodynamic activity, especially at very low ICG concentrations. These preliminary studies indicate the potential of efficient tumor cell delivery and tumoricidal effect of ICG when incorporated in nanoparticles.