Biomedical Photoacoustic Imaging for Molecular Detection and Disease Diagnosis: Always-On and Turn-On Probes

Photoacoustic (PA) imaging is a nonionizing, noninvasive imaging technique that combines optical and ultrasonic imaging modalities to provide images with excellent contrast, spatial resolution, and penetration depth. Exogenous PA contrast agents are created to increase the sensitivity and specificity of PA imaging and to offer diagnostic information for illnesses. The existing PA contrast agents are categorized into two groups in this review: always-on and turn-on, based on their ability to be triggered by target molecules. The present state of these probes, their merits and limitations, and their future development, is explored.

Automated summary

Photoacoustic (PA) imaging is a noninvasive imaging technique that combines optical and ultrasonic imaging modalities to provide high-quality images. This review explores the current state of exogenous PA contrast agents, their merits and limitations, and their future development, categorizing them into always-on and turn-on based on their activation mechanism.