Polyethylene Glycol-Stabilized Gold Nanostars-Loaded Microneedles for Photothermal Therapy of Melanoma

Gold nanostars (GNSs) as a photothermal agent have shown great potential for the treatment of cancers like melanoma. Irradiation of the photothermal agents with light of a suitable wavelength generates heat that induces cellular stress and protein denaturation in cancer cells. The delivery of GNSs to skin using fast dissolving microneedles (MNs) presents a promising approach for painless and convenient administration of the therapy. In this study, polyethylene glycol (PEG) stabilized GNSs able to absorb light in the near-infra red region and release heat (up to 65 degrees C, room temperature) are developed. The cytotoxicity of these nanoparticles is assessed before and after exposure to laser irradiation. GNSs show an instant lethal photothermal effect when tested on B16F10 melanoma cells upon irradiation with 808 nm at a power of 800 mW for 10 min. Loading the GNSs in polyvinylpyrrolidone (PVP) MNs preserves the photothermal effect of GNS and the mechanical properties of MNs. GNS-loaded PVP MNs show efficient piercing in excised porcine skin, fast dissolution in 3 min after insertion and elevation of the skin temperature after laser irradiation (808 nm, 800 mW, 10 min) to 63 degrees C. Consequently, PEG-stabilized GNSs and PVP MNs are a promising platform for photothermal therapy in melanoma treatment. PEG-stabilized gold nanostars (GNSs) are prepared for melanoma treatment via photothermal therapy. GNSs heat generation upon near-infrared irradiation are demonstrated to have a lethal effect on melanoma cells. GNSs' integration in fast-dissolving PVP microneedles are shown to have effective transdermal delivery, and thus, such combination platform of GNSs and PVP microneedles are promising for cancer melanoma treatment.image