Yi Zhang¹, Philipp Gutruf², Daniel Castro³, Michael R. Bruchas³ and John A. Rogers⁴, (1)Material Science and Engineering/Center for Bio-Integrated Electronics, Northwestern University, Evanston, IL, (2)Material Science and Engineering, Northwestern University, Evanston, IL, (3)Anesthesiology and Neurobiology, Washington University in St. Louis, St. Louis, MO, (4)Materials Science and Engineering, Biomedical Engineering and Neurological Surgery (and by courtesy Electrical Engineering and Computer Science, Mechanical Engineering and Chemistry), Northwestern University, Evanston, IL