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Abstract
Stroke ranks at the second leading cause of death and the leading cause of disability amongst adults worldwide according to the World Health Organization. During past several decades, the use of nanotechnology based method to improve stroke treatment has attracted a lot of research attentions. Up to now, tissue plasminogen activator (tPA) is the only Food and Drug Administration proved drug for the treatment of ischemic stroke. However, the side effects such as symptomatic intracranial hemorrhages showed on some patients during tPA treatment have brought major concerns about its safety and efficacy. This dissertation focuses on the fundamental study on how to reduce the risks associated with tPA treatment by improving tPAs effectiveness using magnetic nanomotors.When the concentration of tPA is low, which is common for clinic stroke treatment, the tPA mediated thrombolysis process is a diffusion limited bio-chemical reaction. By accelerating the diffusion of tPA with rotating Ni nanomotors, we have experimentally demonstrated that the thrombolysis rate can be doubled. A theoretical hydrodynamic model is developed to reveal the fundamental physical processes. To further reduce the risks of tPA treatment, Fe3O4 nanorods are fabricated and loaded with 6% mass ratio of tPA and can release tPA in several hours, and the release rate can be further accelerated by an external rotating magnetic field. This method can significantly reduce the amount of tPA administrated in a stroke treatment.This dessication work lay a solid foundation for using magnetic nanomotors to effectively treat stroke and may benefit people who suffering thrombotic diseases.