Metal Complexes and Nanoparticles for Photoacoustic Imaging.

Clinical imaging techniques are widely used to detect, locate, and track the growth or shrinkage of cancerous tumors. Although these techniques have shown impressive results, they often come with health risks due to the use of toxic contrast agents or ionizing radiation. To address these limitations, research efforts have been focused on the development of new imaging techniques. Among the emerging medicinal methods, photoacoustic imaging is receiving much attention. This method effectively combines the most important benefits of both ultrasound and fluorescence imaging, while minimizing their respective drawbacks via a light-in and ultrasound-out approach. This review article focuses on the fundamental concept, recent advances, and strategies for novel contrast agents based on molecular metal complexes or metallic nanoparticles for use in photoacoustic imaging.