In vitro activation of human platelets triggered and probed by atomic force microscopy.

We report on the activation of human platelets probed by atomic force microscopy under nearly physiological conditions. We could image native platelets in different stages of activation at a resolution of about 100 nm. Intracellular structures within the platelets could be resolved without staining. Furthermore we could trigger and follow the activation process of individual platelets, demonstrating that the platelets are still intact and are not destroyed or severely harmed by this novel imaging process.