Despite novel methods are being developed , they usually rely on in vitro measurements, which is far from physiological conditions: in normal vessels, platelet activation is constantly inhibited, primarily by NO constantly released by endothelial cells. Concentration of NO as low as 3-90 nM effectively inhibits platelet activation , and attempts to study platelet activation using exogenous NO donors were made . Light-activatable NO donors are promising in this respect because they provide steady and controllable release. In this study, we used compound BODIPY-NOD-2 as NO photodonor.