Poly(ε-caprolactone) (PCL) fibers incorporated with phase-changeable fatty acid and indocyanine green for NIR light-triggered, localized anti-cancer drug release

This paper describes a new system for NIR light-triggered, localized release of drugs. The system consists of biocompatible/degradable poly(ε-caprolactone) (PCL)-based fibers having a core loaded with doxorubicin (DOX) and a sheath incorporated with indocyanine green (ICG) as a NIR-absorbing agent together with a biocompatible/degradable, phase-changeable fatty acid. Upon NIR irradiation, the photothermal agent will generate heat to raise the local temperature of the fibers. When the temperature is above the melting point of the fatty acid, nano-pores will be generated in the fibers. This response to NIR irradiation allows the instant release of DOX from the fibers through the pores, leading to the significant enhancement of anticancer activity in combination with the hyperthermia effect arising from the photothermal agent.