From Locomotion to Biomedical Applications

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From Locomotion to Biomedical Applications UNIVERSITY OF CALIFORNIA, SAN DIEGO Micro/Nanorobotics: from Locomotion to Biomedical Applications A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Nano Engineering by Jinxing Li Committee in charge: Professor, Joseph Wang, Chair Professor, Ying Shirley Meng Professor, David Saintillan Professor, Mike Tolley Professor, Liangfang Zhang 2017 © Jinxing Li, 2017 All rights reserved. The Dissertation of Jinxing Li is approved, and it is acceptable in quality and form for publication on microfilm and electronically: Chair University of California, San Diego 2017 iii DEDICATION To my mom and dad. iv EPIGRAPH “The mountains are calling and I must go.” - John Muir “Having fun, this is the most important.” - Joseph Wang v TABLE OF CONTENTS SIGNATURE PAGE ...................................................................................................................... iii DEDICATION ................................................................................................................................ iv EPIGRAPH ...................................................................................................................................... v TABLE OF CONTENTS ................................................................................................................ vi LIST OF FIGURES ......................................................................................................................... x ACKNOWLEDGEMENTS .......................................................................................................... xiii VITA ............................................................................................................................................. xvi ABSTRACT OF THE DISSERTATION .................................................................................... xvii Chapter 1 Introduction ..................................................................................................................... 1 1.1 Motivations, challenges, and solutions for nanolocomotion .................................................. 1 1.2 Biomedical applications of micro/nanorobots ....................................................................... 5 1.2.1 Micro/Nanorobots for Targeted Delivery ....................................................................... 6 1.2.2 Precision Surgery ............................................................................................................ 8 1.2.3 Biosensing ..................................................................................................................... 10 1.2.4 Detoxification ............................................................................................................... 11 1.3 Other applications of micro/nanorobots ............................................................................... 12 1.3.1 Environmental applications........................................................................................... 12 1.3.2 Defense applications ..................................................................................................... 13 1.3.3 Energy applications ....................................................................................................... 14 1.3.4 Nanomanipulation and assembly .................................................................................. 15 1.3.5 Active and living matter ................................................................................................ 16 1.4 References ............................................................................................................................ 19 Chapter 2 Inspired from the Nature: Wireless Nanorobots Actuated by External Fields ............. 25 2.1 Template electrosynthesis of tailored-made helical nanoswimmers .................................... 25 2.1.1 Introduction ................................................................................................................... 25 2.1.2 Experimental Section .................................................................................................... 27 2.1.3 Template-assisted electrodeposition ............................................................................. 29 2.1.4 Magnetic actuation of the helical nanoswimmers ......................................................... 34 vi 2.1.5 Conclusions ................................................................................................................... 36 2.2 Magneto-acoustic hybrid nanomotor ................................................................................... 37 2.2.1 Introduction ................................................................................................................... 37 2.2.2 Experimental section ..................................................................................................... 38 2.2.3 Hybrid nanomotor design and fabrication .................................................................... 40 2.2.4 Adaptive actutation of hybrid nanomotors .................................................................... 43 2.2.5 Collective behaviours of hybrid nanomotors ................................................................ 51 2.2.6 Conclusion .................................................................................................................... 56 2.3 Biointerfacing magnetic nanorobots with platelet membrane for biothreat isolation .......... 58 2.3.1 Introduction ................................................................................................................... 58 2.3.2 Experimental Section .................................................................................................... 60 2.3.3 Preparation and characterization of PL-motors ............................................................. 64 2.3.4 Propulsion performance and anti-biofouling capacity of PL-motors ............................ 68 2.3.5 Shiga toxin binding and detoxification ......................................................................... 69 2.3.6 Platelet-adhering pathogens binding and isolation ....................................................... 72 2.3.7 Conclusions ................................................................................................................... 73 2.4 References ............................................................................................................................ 75 Chapter 3 State of the Art: Technical Applications of Micro/Nanorobots ................................... 82 3.1 Nanorobot to write: nanomotor lithography ........................................................................ 82 3.1.1 Introduction ................................................................................................................... 82 3.1.2 Experimental methods .................................................................................................. 83 3.1.3 Nanomotor lithography concept and optical simulation ............................................... 86 3.1.4 Patterning by metallic nanowire motors ....................................................................... 88 3.1.5 Remote magnetically-guided writing ............................................................................ 90 3.1.6 Patterning by Janus sphere motors ................................................................................ 92 3.1.7 Conclusion .................................................................................................................... 96 3.2 Nanorobot to read: swimming microrobot optical nanoscopy ............................................. 97 3.2.1 Introduction ................................................................................................................... 97 3.2.2 Experimental section ..................................................................................................... 98 3.2.3 Scanning with Single Microrobot ............................................................................... 101 3.2.4 Large-area and parallel scanning ................................................................................ 103 3.2.5 Magnification capacity and scanning rate ................................................................... 105 vii 3.2.6 Imaging of fluorescent and biological samples ........................................................... 107 3.2.7 Conclusion .................................................................................................................. 109 3.3 Nanorobot to repair: Self-propelled nanomotors autonomously seek and repair cracks ... 111 3.3.1 Introduction ................................................................................................................. 111 3.3.2 Experimental section ................................................................................................... 114 3.3.3 Simulation Section ...................................................................................................... 116 3.3.4 Nanomotor localization ............................................................................................... 120 3.3.5 Restoring conductivity of cracked circuits .................................................................. 130 3.3.6 Conclusion .................................................................................................................. 134 3.4 References .........................................................................................................................
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