Development of giant magnetoresistive biosensors and systems for early disease detection

Loading...
Thumbnail Image

Persistent link to this item

Statistics
View Statistics

Journal Title

Journal ISSN

Volume Title

Title

Development of giant magnetoresistive biosensors and systems for early disease detection

Published Date

2018-02

Publisher

Type

Thesis or Dissertation

Abstract

Giant magnetoresistance (GMR) biosensors have been used with great success for the detection of a variety of biomarkers. Linear GMR biosensors were first proposed in 1998 and have been used since then. The major scientific contribution of this dissertation is to go beyond the previously published models for the linear GMR biosensor and provide analysis of practical design decisions that occur during sensor fabrication. I highlight the central role played by GMR free layer stray field near the sensor edge and present a numerical calculation to guide future linear GMR biosensor design. In addition, I explain how I proposed and demonstrated a novel, non-linear, domain-wall based GMR biosensor, in an effort to detect single molecules. I also describe my contributions to an effort to understand and build upon a previous experimental result using a large area sensor with multidomain switching. The major technological contribution described in this dissertation is the development of a GMR biosensing system that can potentially contribute to the early detection of ovarian cancer and serve as a platform for detecting a wide variety of other biomarkers. System integration included spintronic and nanomagnetic materials engineering, design of a coil with a ferrite core, electrical engineering, analog and digital signal processing, firmware programming, user interface programming on both a PC and an Android smartphone, communications over both USB and Bluetooth, and mechanical design. Hand-held and bench-top systems of this GMR bionsensor were both developed. Both versions use the same sensors, electrical hardware, firmware, and software, but differ mechanically and in the number of sensors available per assay. The bench-top version was completed first and used to demonstrate high sensitivity multiplex detection of ovarian cancer biomarkers CA-125, HE-4, and IL-6, with limits of detection below 10 pg/mL. The hand-held version was then completed and used with a preliminary biotin-streptavidin demonstration. Further development of the hand-held system involves integrating microfluidics.

Description

University of Minnesota Ph.D. dissertation. February 2018. Major: Electrical Engineering. Advisor: Jian-Ping Wang. 1 computer file (PDF); xi, 204 pages.

Related to

Replaces

License

Collections

Series/Report Number

Funding information

Isbn identifier

Doi identifier

Previously Published Citation

Suggested citation

Klein, Todd. (2018). Development of giant magnetoresistive biosensors and systems for early disease detection. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/213110.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.