An Efficient Near-Infrared Photothermal Therapy Agent by Using Ag@Oxides Nanoprisms in for Uveal melanoma Therapy

Abstract

Purpose: Photothermal therapy (PTT) have been used in cancer therapy in recent years, however it is a virgin area in the field of ophthalmology. We created a new PTT agent --Silver-oxides core-shell nanoprisms (Ag@oxides NPs) that possess stronger near-infrared (NIR) absorption and higher phototherma conversion efficiency. The purpose of this study was to demonstrate Ag @oxides nanoprisms can be used as an effective PTT agent in vivo and vitro for Uveal melanoma Therapy.

Methods: Ag NPs were synthesized using a seed-mediated procedure. Ag@oxides NPs were prepared via a simple sol-gel route. The thickness of the oxides shell can be precisely tuned from 1 to 15 nm through changing the reaction time and amount of oxides sol-gel precursor. For measuring the photothermal conversion performance of the Ag@oxides core-shell NPs, 1mL aqueous dispersion of Ag@oxides NPs with different concentrations were introduced in a quartz cuvette and irradiated with an 808 nm NIR laser at a power density of 2 W*cm^-2.Cytotoxicity and therapeutic efficiency of Ag NP were tested in OCM-1 cells using MTT assay. C57BL/6J mice were for intraocular melanoma tumor model. The tumor body were injected Ag@oxides NPs then exposed to an 808 nm laser at 2 W*cm^-2 for 30 seconds, immediately. The photothermal effectiveness of Ag NP was evaluated by measuring the size of the tumor.

Results: We developed a facile method to synthesize Ag@oxides core-shell NPs with a tunable shell thickness through the simple sol-gel route. Ag@oxides exhibits a good biocompatiblity and stability for in vivo and vitro due to the existence of oxide shell layer. The localized surface plasmon resonance (LSPR) absorption band of Ag@oxides appeared at approximately 808 nm known as the Near-Infrared Window. When the light at 808 nm illuminated the Ag@oxides NPs, the temperature of media surrounding Ag@oxides NPs rapidly rose up, resulting in significant OCM-1 cells death in Ag NPs-treated(100 μg·mL⁻¹) in vitro (p<0.01). The tumor size of Ag NPs + laser group were significantly less than other groups in three days after treatment (P<0.001). The cells showed well tolerated to Ag@oxides NPs and the mice remained healthy over one-month period.

Conclusions: Ag@oxides NPs were demonstrated to be an efficient photothermal therapy agent for solid cancers by local delivery.