Copper Sulfide Small Nanoparticles as Efficient Contrast Agent for Photoacoustic Imaging

An experimental study on an innovative contrast agent is presented. This work demonstrates that copper sulfide in the form of small-sized nanoparticles can be exploited in photoacoustic imaging. An advantage of this material is strong light absorption in the near-infrared range, especially in the transparency windows of biological tissues. In order to yield a proper contrast, light absorption must be followed by heat release with high efficiency. Therefore, it is important to evaluate the photochemical conversion efficiency of the material. We applied a method that is strictly related to photoacoustic applications. The nanoparticles were produced according to a well-established synthesis. Subsequently, they were diluted in pure water to obtain an extinction