Skin-safe Photothermal Therapy Upon Very Low Laser Irradiation

How to ablate tumor without damaging skin is a challenge for photothermal therapy.We herein show skin-safe photothermal cancer therapy provided by the responsive release of acid-activated hemolytic polymer(aHLP)from the photothermal polydopamine(PDA)nanoparticle upon irradiation at very low dosage.Upon skin－permissible irradiation(with an 850-nm laser irradiation at power density of 0.4 W/cm2)our nanoparticle aHLP-PDA generates sufficient localized-heat to bring about mild hyperthermia treatment and consequently responsively shed off aHLP polymer from its PDA nanocore leading to demonstrated cytotoxicity selective to cancer cells at acidic pH characteristic of tumor extracellular microenvironememt.As a result our aHLP-PDA nanoparticle upon irradiation at such low dosage effectively inhibits tumor growth without damaging skin as demonstrated with animal models.Effective in mitigating the otherwise inevitable skin damage in tumor photothermal therapy the nanosystem reported herein offers an efficient pathway towards skin-safe photothermal therapy.