Some users are experiencing upload errors at the moment. If you receive a "UWSpace is down for maintenance" error, please email jordan.hale@uwaterloo.ca as soon as possible. We are very sorry for the inconvenience.

Show simple item record

dc.contributor.authorSun, Weien
dc.date.accessioned2007-05-08 14:07:23 (GMT)
dc.date.available2007-05-08 14:07:23 (GMT)
dc.date.issued2006en
dc.date.submitted2006en
dc.identifier.urihttp://hdl.handle.net/10012/2984
dc.description.abstractIn this thesis, a novel electrochemical array is reported. The array consists of two planar halves, each having four carbon screen-printed band electrodes (SPEs), orthogonally facing each other and separated by a spacer to yield 16 two-electrode electrochemical cells with 1 mm<sup>2</sup> working electrode areas. The 16 counter electrodes were converted to Ag/AgCl by electrodeposition and anodization. These electrodes were stable for at least 30 days with potentials under the current densities used in our experiments. The 16 working electrodes were modified by Au electrodeposition, and were examined by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). <br /><br /> Immobilization strategies for biomolecules are of paramount importance for successful fabrication of biosensors. This thesis reports a new immobilization method that is based on patterned deposition of alkyl thiosulfates (Bunte salts). Monolayers were formed through electrochemical oxidation of Bunte salts at Au-modified electrodes. Single-component and mixed monolayers were investigated, where the mixed monolayers involved one component with a terminal carboxylic acid functional group to allow immobilization of biomolecules. <br /><br /> Applications of the newly developed immobilization method to an enzyme-based biosensor and an immunosensor were investigated. Glucose and biotin were chosen as model analytes, respectively. Glucose oxidase (GOx) and avidin were covalently immobilized onto the mixed-monolayer-modified electrodes through the carboxylic acid groups. Under the optimized conditions for the fabrication and operation of the biosensors, the new electrochemical array showed linearity up to 10 mM glucose with a sensitivity of 4. 7 nA mM<sup>-1</sup> and a detection limit of 0. 8 mM (S/N=3), and linearity up to 12. 8 µM biotin with a detection limit of 0. 08 µM (S/N=3).en
dc.formatapplication/pdfen
dc.format.extent3369505 bytes
dc.format.mimetypeapplication/pdf
dc.language.isoenen
dc.publisherUniversity of Waterlooen
dc.rightsCopyright: 2006, Sun, Wei. All rights reserved.en
dc.subjectChemistryen
dc.subjectbiosensorsen
dc.subjectmonolayeren
dc.subjectglucose oxidaseen
dc.subjectimmobilizationen
dc.subjectBunte saltsen
dc.titleBiosensing at an individually addressable electrochemical arrayen
dc.typeDoctoral Thesisen
dc.pendingfalseen
uws-etd.degree.departmentChemistry and Biochemistryen
uws-etd.degreeDoctor of Philosophyen
uws.typeOfResourceTexten
uws.peerReviewStatusUnrevieweden
uws.scholarLevelGraduateen


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record


UWSpace

University of Waterloo Library
200 University Avenue West
Waterloo, Ontario, Canada N2L 3G1
519 888 4883

All items in UWSpace are protected by copyright, with all rights reserved.

DSpace software

Service outages