Microfluidic chips for combinatorial screening applications

Schudel, Benjamin R.

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https://hdl.handle.net/2142/16107 Copy

Description

Title

Microfluidic chips for combinatorial screening applications

Author(s)

Schudel, Benjamin R.

Issue Date

2010-05-19T18:36:25Z

Director of Research (if dissertation) or Advisor (if thesis)

Kenis, Paul J.A.

Doctoral Committee Chair(s)

Kenis, Paul J.A.

Committee Member(s)

• Zhao, Huimin
• Cunningham, Brian T.
• Schroeder, Charles M.

Department of Study

Chemical & Biomolecular Engr

Discipline

Chemical Engineering

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

• microfluidics
• combinatorial chemistry
• Total internal reflection fluorescence (TIRF)
• microscopy
• photonic crystals
• biosensors

Abstract

A wealth of small molecule compounds exist that may inhibit cancer or virus-causing diseases, and a wide array of experiments must be performed to narrow down the hundreds of thousands of possible candidates to a few biologically relevant compounds that could serve as ideal drug candidates. Microscale systems have the ability to duplicate benchtop screening experiments with the same fidelity at much smaller scales. Microscale experiments also have the benefit of using very little precious reagent, giving the economic value of low volume usage. In order to develop high density microscale experimental combinatorics, a new valve was developed that is passively closed at rest, termed Actuate-to-Open (AtO) valves. Chapter 2 reports new design rules for AtO valve operation, both in single valve studies and in large on-chip arrays. The AtO valves are also employed in a combinatorial screening chip with a reversible seal that allows for interchangeable sensing capabilities. In Chapter 3, the combinatorial screening chip is integrated with a photonic crystal biosensor capable of screening for binding events in a label free fashion. A proof-of-principle protein-antibody assay was performed to validate the combinatorial features of the chip. In Chapter 4, the combinatorial chip was integrated with a molecular beacon patterned glass cover slip capable of detecting complimentary DNA fragments. Total internal reflection fluorescence (TIRF) microscopy is used for read out of the chip. Four virus-like oligomer targets with sequences corresponding to key fragments of the viruses HIV, HPV, Hepatitis A and Hepatitis B were tested against four different molecular beacons, each complementary to one of the four virus target oligonucleotides. The result of this combinatorial screening chip indicated strong fluorescent values for the matching beacon-target pairs, with statistically insignificant values for non-matching targets. This experiment not only established proof of principle of on-chip virus detection, it also demonstrated the high specificity of surface immobilized molecular beacons used in combination with TIRF.

Graduation Semester

2010-5

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http://hdl.handle.net/2142/16107

Copyright and License Information

Copyright 2010 Benjamin Schudel

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