Arresting Alzheimer's

scientists have developed a new dye that could offer non-invasive early diagnosis of Alzheimer's disease, a discovery that could aid in monitoring the progression of the disease and in studying the efficacy of new treatments to stop it. The work is published in the latest issue of

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Today, doctors can only make a definitive diagnosis of Alzheimer's, currently the fourth-leading cause of death in the United States, through a post-mortem autopsy of the brain. "Before you can cure Alzheimer's, you have to be able to diagnose it and monitor its progress very precisely," said Timothy Swager, leader of the work and a professor in MIT's Department of Chemistry. "Otherwise it's hard to know whether a new treatment is working or not."

To that end, Swager and postdoctoral associate Evgueni Nesterov, also from the MIT Department of Chemistry, worked with researchers at Massachusetts General Hospital and the University of Pittsburgh to develop a contrast agent that would first bind to the protein deposits, or plaques, in the brain that cause Alzheimer's, and then fluoresce when exposed to radiation in the near-infrared range. The new dye could allow direct imaging of Alzheimer's plaques through a patient's skull.