            †   †               !"  #$% 1 Department of Bioengineering Engineering, University of California, Berkeley, CA 94720, USA 2 Berkeley Sensor and Actuator Center, University of California, Berkeley, CA 94720, USA  Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 121$742, Korea 4 Department of Life science, University of Seoul, Seoul 130$743, Korea # Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA 94720, USA 6 Biophysics Graduate Program, University of California, Berkeley, CA 94720, USA %&&’( )* +,-* -’-./&-" 0"!"1