Skip to Main Content
 

Global Search Box

 
 
 
 

Files

ETD Abstract Container

Abstract Header

Development of Electrochemical Sensors for Biodegradable Metallic Implants and Development of a Label-free Biosensor for Bacteria

Abstract Details

2012, PhD, University of Cincinnati, Arts and Sciences: Chemistry.

This dissertation describes development and characterization of the electrochemical sensors for studying the corrosion of biodegradable metallic implant for the overall RMB research project and electrochemical biosensors for the detection of bacteria. Specifically, three major projects were done. The first involved fabrication and characterization of electrochemical sensors for the cations Zn2+, Ca2+, Mg2+, and H+ using carbon nanotubes (CNTs). Detection of Zn2+ was based on an ASV sensor at a CNT tower electrode with a detection limit of 67 nM without any toxic additives. Sensors for the cations Ca2+, Mg2+, and H+ were solid contact-ion selective electrode (SC-ISE) based on CNT towers. SC-ISE can detect Ca2+ as low as 1.6 ¿¿¿¿M with a stable potential for up to three weeks. These electrodes can detect other cations by changing the sensing membrane.

The second part was the development of three systems to study the corrosion of biodegradable metallic implants: corrosion characterization system (CCS), static in vitro CCS, and dynamic in vitro CCS. Multiple appropriate sensors were chosen and applied to these three systems to monitor the degradation of Mg alloy simultaneously and continuously.

The third part was the development of label-free biosensor for bacteria based on faradaic EIS as a spin-off project of RMB. a-Mannoside was immobilized on a gold disk electrode using a SAM via a spacer terminated in a thiol functionality. A linear relationship between normalized Ret and the logarithmic value of E. coli concentrations was found in a range of bacterial concentration from 102 to 103 CFU/mL. The combination of robust carbohydrate ligands with EIS provides a label-free, sensitive, specific, user-friendly, robust, and portable biosensing system that could potentially be used in point-of-care or continuous environmental monitoring settings.

The development of electrochemical sensors based on advanced carbon materials and the development of three testing systems (CCS, static in vitro CCS and dynamic in vitro CCS) show new testing methods for biodegradable metallic implants, especially for Mg alloys. The preliminary results presented in this dissertation show that it is possible to monitor corrosion of Mg alloys using two or three electrochemical sensors simultaneously. In the future, the integration of more electrochemical sensors including the developed sensors in Chapter 2 and Chapter 3 will provide more information about the corrosion. With this purpose, the developed electrochemical sensors in Chapter 2 and Chapter 3 should be studied more with respect to selectivity and biofouling in biological applications.

William Heineman, PhD (Committee Chair)
Hairong Guan, PhD (Committee Member)
Thomas Ridgway, PhD (Committee Member)
160 p.

Recommended Citations

Citations

  • Guo, X. (2012). Development of Electrochemical Sensors for Biodegradable Metallic Implants and Development of a Label-free Biosensor for Bacteria [Doctoral dissertation, University of Cincinnati]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1342106824

    APA Style (7th edition)

  • Guo, Xuefei. Development of Electrochemical Sensors for Biodegradable Metallic Implants and Development of a Label-free Biosensor for Bacteria. 2012. University of Cincinnati, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=ucin1342106824.

    MLA Style (8th edition)

  • Guo, Xuefei. "Development of Electrochemical Sensors for Biodegradable Metallic Implants and Development of a Label-free Biosensor for Bacteria." Doctoral dissertation, University of Cincinnati, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1342106824

    Chicago Manual of Style (17th edition)