Blending Low‐Frequency Vibrations and Push–Pull Effects Affords Superior Photoacoustic Imaging Agents
Le Yu, Syed Ali Abbas Abedi, Jeongjin Lee, Yunjie Xu, Subin Son, Weijie Chi, Mingle Li, Xiaogang Liu, Jae Hyung Park, Jong Seung Kim
Abstract
Abstract Photoacoustic imaging (PAI), a state‐of‐the‐art noninvasive in vivo imaging technique, has been widely used in clinical disease diagnosis. However, the design of high‐performance PAI agents with three key characteristics, i.e., near‐infrared (NIR) absorption (λ abs >800 nm), intense PA signals, and excellent photostability, remains a challenging goal. Herein, we present a facile but effective approach for engineering PAI agents by amplifying intramolecular low‐frequency vibrations and enhancing the push‐pull effect. As a demonstration of this blended approach, we constructed a PAI agent ( BDP1‐NEt 2 ) based on the boron‐dipyrromethene (BODIPY) scaffold. Compared with indocyanine green (ICG, an FDA‐approved organic dye widely utilized in PAI studies; λ abs =788 nm), BDP1‐NEt 2 exhibited a UV/Vis‐NIR spectrum peaked at 825 nm, superior in vivo PA signal intensity and outstanding stability to offer improved tumor diagnostics. We believe this work provides a promising strategy to develop the next generation of PAI agents.