IN SITU ELECTROKINETIC SAMPLE PREPARATION FOR SELF-ASSEMBLED MONOLAYER BASED ELECTROCHEMICAL BIOSENSING

Persistent Link:
http://hdl.handle.net/10150/205176
Title:
IN SITU ELECTROKINETIC SAMPLE PREPARATION FOR SELF-ASSEMBLED MONOLAYER BASED ELECTROCHEMICAL BIOSENSING
Author:
Sin, Lai Yi Mandy
Issue Date:
2011
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Embargo:
Embargo: Release after 07/20/2012
Abstract:
Electrokinetics based microfluidic systems are potentially promising for lab-on-a-chip applications due to their effectiveness in manipulating nanoscale and biological objects, label-free operation, simple fabrication processes, small voltage requirements, and most importantly simple system integration strategy. Among various electrokinetics techniques, AC electrothermal flow (ACEF) is the most promising technique in microfluidic manipulation toward biomedical applications due to its effectiveness in high conductivity biological and physiological fluids. As relatively little is known about the ACEF induced fluid motion at highly conductive samples, the characteristics of electrothermal manipulation of fluid samples with different conductivities were investigated systematically. For low conductivity sample (below 1 S/m), the characteristics of the electrothermal fluid motion was in quantitative agreement with the theory. For high conductivity samples (greater than 1 S/m), the fluid motion appeared to deviate from the model as a result of electrochemical reactions and the temperature effect. Here, a universal electrode approach which directly implements ACEF-induced sample preparation on a SAM based electrochemical sensor for point-of-care diagnostics of urinary tract infections has also been demonstrated. Using uropathogenic E. coli clinical isolates as model systems, we demonstrate that "on-chip" ACEF-induced sample preparation can improve the sensor performance without complicated system integration strategy and presents a pathway for implementing truly lab on a chip, instead of chip in a lab. Finally an integrated chip approach has been proposed for transforming electrochemical sensing system from laboratory research into point-of-care diagnostics with multiple microelectrodes.
Type:
text; Electronic Dissertation
Keywords:
Sample Preparation; Mechanical Engineering; Electrochemical Biosensing; Electrokinetic
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Mechanical Engineering
Degree Grantor:
University of Arizona
Advisor:
Wong, Pak Kin

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleIN SITU ELECTROKINETIC SAMPLE PREPARATION FOR SELF-ASSEMBLED MONOLAYER BASED ELECTROCHEMICAL BIOSENSINGen_US
dc.creatorSin, Lai Yi Mandyen_US
dc.contributor.authorSin, Lai Yi Mandyen_US
dc.date.issued2011-
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.releaseEmbargo: Release after 07/20/2012en_US
dc.description.abstractElectrokinetics based microfluidic systems are potentially promising for lab-on-a-chip applications due to their effectiveness in manipulating nanoscale and biological objects, label-free operation, simple fabrication processes, small voltage requirements, and most importantly simple system integration strategy. Among various electrokinetics techniques, AC electrothermal flow (ACEF) is the most promising technique in microfluidic manipulation toward biomedical applications due to its effectiveness in high conductivity biological and physiological fluids. As relatively little is known about the ACEF induced fluid motion at highly conductive samples, the characteristics of electrothermal manipulation of fluid samples with different conductivities were investigated systematically. For low conductivity sample (below 1 S/m), the characteristics of the electrothermal fluid motion was in quantitative agreement with the theory. For high conductivity samples (greater than 1 S/m), the fluid motion appeared to deviate from the model as a result of electrochemical reactions and the temperature effect. Here, a universal electrode approach which directly implements ACEF-induced sample preparation on a SAM based electrochemical sensor for point-of-care diagnostics of urinary tract infections has also been demonstrated. Using uropathogenic E. coli clinical isolates as model systems, we demonstrate that "on-chip" ACEF-induced sample preparation can improve the sensor performance without complicated system integration strategy and presents a pathway for implementing truly lab on a chip, instead of chip in a lab. Finally an integrated chip approach has been proposed for transforming electrochemical sensing system from laboratory research into point-of-care diagnostics with multiple microelectrodes.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectSample Preparationen_US
dc.subjectMechanical Engineeringen_US
dc.subjectElectrochemical Biosensingen_US
dc.subjectElectrokineticen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineMechanical Engineeringen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorWong, Pak Kinen_US
dc.contributor.committeememberChan, Cho Liken_US
dc.contributor.committeememberZohar, Yitshaken_US
dc.contributor.committeememberWong, Pak Kinen_US
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