Copper sulfide nanoparticles for photothermal ablation of tumor cells

Aims: Copper sulfide (CuS) nanoparticles were developed as a new type of agent for photothermal ablation of cancer cells. Materials & methods: CuS nanoparticles were synthesized by wet chemistry and their application in photothermal ablation of tumor cells was tested by irradiation using a near-infrared (NIR) laser beam at 808 nm to elevate the temperature of aqueous solutions of CuS nanoparticles as a function of exposure time and nanoparticle concentration. CuS nanoparticle-mediated photothermal destruction was evaluated using human cervical cancer HeLa cells with respect to laser dose and nanoparticle concentration. Their toxicity was evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Results: CuS nanoparticles have an optical absorption band in the NIR range with a maximum absorbance at 900 nm. Irradiation by a NIR laser beam at 808 nm resulted in an increase in the temperature of the CuS nanoparticle aqueous solution as a function of exposure time and nanoparticle concentration. CuS nanoparticle-induced photothermal destruction of HeLa cells occured in a laser dose- and nanoparticle concentration-dependent manner, and displayed minimal cytotoxic effects with a profile similar to that of gold nanoparticles. Conclusion: Owing to their unique optical property, small size, low cost of production and low cytotoxicity, CuS nanoparticles are promising new nanomaterials for cancer photothermal ablation therapy.