Photothermal theragnosis synergistic therapy based on bimetal sulphide nanocrystals rather than nanocomposites.

A new generation of photothermal theranostic agents is developed based on Cu3BiS3 nanocrystals. A computed tomography imaging response and photothermal effect, as well as near-infrared fluorescence emission, can be simultaneously achieved through Cu3BiS3 nanocrystals rather than frequently used nanocomposites. These results provide some insight into the synergistic effect from bimetal sulphide semiconductor compounds for photothermal theragnosis therapy.

Facile synthesis of biocompatible cysteine-coated CuS nanoparticles with high photothermal conversion efficiency for cancer therapy.

The semiconductor compounds have been proven to be promising candidates as a new type of photothermal therapy agent, but unsatisfactory photothermal conversion efficiencies limit their widespread application in photothermal therapy (PTT). Herein, we synthesized cysteine-coated CuS nanoparticles (Cys-CuS NPs) as highly efficient PTT agents by a simple aqueous solution method. The Cys-CuS NPs have a good biocompatibility owing to their biocompatible cysteine coating and exhibit a strong absorption in the near-infrared region due to the localized surface plasma resonances of valence-band free carriers. The photothermal conversion efficiency of Cys-CuS NPs reaches 38.0%, which is much higher than that of the recently reported Cu9S5 and Cu(2-x)Se nanocrystals. More importantly, tumor growth can be efficiently inhibited in vivo by the fatal heat arising from the excellent photothermal effect of Cys-CuS NPs at a low concentration under the irradiation of a 980 nm laser with a safe power density of 0.72 W cm(-2). Therefore, the Cys-CuS NPs have great potential as ideal photothermal agents for cancer therapy.

Cu2-xSe@mSiO2-PEG core-shell nanoparticles: a low-toxic and efficient difunctional nanoplatform for chemo-photothermal therapy under near infrared light radiation with a safe power density.

A low-toxic difunctional nanoplatform integrating both photothermal therapy and chemotherapy for killing cancer cells using Cu2-xSe@mSiO2-PEG core-shell nanoparticles is reported. Silica coating and further PEG modification improve the hydrophilicity and biocompatibility of copper selenide nanoparticles. As-prepared Cu2-xSe@mSiO2-PEG nanoparticles not only display strong near infrared (NIR) region absorption and good photothermal effect, but also exhibit excellent biocompatibility. The mesoporous silica shell is provided as the carrier for loading the anticancer drug, doxorubicin (DOX). Moreover, the release of DOX from Cu2-xSe@mSiO2-PEG core-shell nanoparticles can be triggered by pH and NIR light, resulting in a synergistic effect for killing cancer cells. Importantly, the combination of photothermal therapy and chemotherapy driven by NIR radiation with safe power density significantly improves the therapeutic efficacy, and demonstrates better therapeutic effects for cancer treatment than individual therapy.

Cu7.2S4 nanocrystals: a novel photothermal agent with a 56.7% photothermal conversion efficiency for photothermal therapy of cancer cells.

Copper sulphides, as a novel kind of photothermal agent for photothermal therapy (PTT) of cancer cells, have attracted increasing attention in recent years due to good photostability, synthetic simplicity, low toxicity and low cost. However, the unsatisfactory photothermal conversion efficiency of copper sulphides limits their bioapplication as PTT agents. Herein, Cu7.2S4 NCs with a mean size of ∼20 nm as a novel photothermal agent have been prepared by a simple thermal decomposition route. Moreover, these NCs exhibit strong near-infrared (NIR) absorption, good photostability and significant photothermal conversion efficiency up to 56.7% due to strong NIR absorption, good dispersity and suitable size. Importantly, these NCs can be very compatibly used as a 980 nm laser-driven PTT agent for the efficient PTT of cancer cells in vitro and in vivo.