Optimizing magnetomotive contrast of SPIO-labeled platelets for thrombosis imaging in optical coherence tomography.

Rehydratable, lyophilized platelets loaded with superparamagnetic iron oxides (SPIOs) has the potential to provide magnetomotive imaging contrast to sites of vascular damage, including thrombosis complicating atherosclerosis and hemorrhage. Magnetomotive optical coherence tomography (MMOCT) contrasts SPIO-platelets based on their nanoscale, magnetically-induced motion. We report improvements in MMOCT imaging contrast and sensitivity by optimizing the magnetic properties and SPIO loading of the platelets. SPIO-platelets have been shown to specifically adhere to sites of vascular damage in porcine arteries ex vivo. This may lead to new methods for detecting internal bleeding and monitoring the formation of blood clots using infused SPIO-platelets.