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Surface Optofluidic Implementations towards the Development of a Biosensor


Choi, Jae-Woo (2011) Surface Optofluidic Implementations towards the Development of a Biosensor. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/KYZG-3503.


Microfluidics is a multidisciplinary field that uses minute volumes of liquids to attempt complex functionalities. These complicated functionalities often require manipulating interfaces through external forces. In addition, optics have become a fundamental necessity for most microfluidic devices. We combine these two concepts and call it surface optofluidics. Here, we focus on the advantages of surface optofluidics for the development of a biosensor, specifically focusing on the flexibility and adaptability offered by these techniques.

To introduce the advantages presented by surface optofluidics, devices using droplet electrowetting techniques are discussed. We then discuss biosensing through structured electrodes on surfaces. The electrodes are used to align asymmetric bacteria. The aligned bacteria are detected optically. This method of detection is improved by incorporating two different surface optofluidic methods. Concentration and motion control of the bacterium is demonstrated with electric fields on three dimensionally structured electrodes and an optothermal nanoparticle carpet. Finally, we show preliminary work in the study of single bacterium behavior using nanoparticles as labels to detect its specific alignment in space.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:microfluidics, optofluidics, biosensing, dielectrophoresis, electroorientation, plasmonics, photothermal, electrowetting, bacteria, nanowire
Degree Grantor:California Institute of Technology
Division:Engineering and Applied Science
Major Option:Electrical Engineering
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Psaltis, Demetri
Thesis Committee:
  • Psaltis, Demetri (chair)
  • Yang, Changhuei
  • Perona, Pietro
  • Willis, Peter
Defense Date:16 March 2011
Non-Caltech Author Email:choijw (AT)
Record Number:CaltechTHESIS:03242011-165209307
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:6273
Deposited By: Jae-Woo Choi
Deposited On:27 May 2011 21:02
Last Modified:09 Oct 2019 17:08

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