Light-Controlled Platelet Mechanics with Tunable BODIPY Photosensitizers

Reactive oxygen species (ROS) are key modulators of cellular signaling, yet their direct influence on the integrin force transmission in platelets is poorly understood. Here, we combine molecular spectroscopy with integrin tension mapping to establish a mechanistic link between singlet oxygen (¹O₂) generation and platelet mechanics. A series of BODIPY-based photosensitizer conjugates were synthesized and systematically characterized by steady-state absorption, emission, and lifetime studies. The iodine-substituted derivative showed the highest intersystem crossing efficiency and ¹O₂ quantum yield, outperforming their fluorine- and methyl-substituted counterparts. When applied to human platelets, enhanced ROS production correlated with reduced integrin forces, impaired spreading, and diminished aggregation. These findings define a direct spectroscopy-to-mechanobiology correlation, connecting the photophysical properties of ROS-generating dyes with platelet mechanotransduction. This work identifies oxidative stress as a regulator of platelet force transmission and provides a framework for designing redox-based molecular probes and therapeutic strategies.