Using click chemistry to study the photoacoustic effect of near-infrared captivating pyrene derivatives

Near-infrared photoacoustic (PA) imaging usually employs near-infrared light-absorbing agents to detect cancer cells/tissue by generating acoustic energy from optical energy. Here, a class of near-infrared dyes, pyrene derivatives with different substitutes, was characterized by PA technology. Interestingly, the click reagents F4-TCNQ could cause the redshift of peaks of the PA intensity of pyrene derivatives. Besides, the symmetric pyrene derivatives had a better PA effect, pyrene accumulation of benzene ring structure also had a certain influence on the PA effect. The systematical study of the near-infrared dyes not only showed the high potential of pyrene derivatives as PA contrast agents but also gave guidelines for designing near-infrared absorbing dyes for high PA intensity in the future.