Graduate Studies


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Document Type



Mayer, M. D. and Lai, R. Y. Effect of the Redox Label Location on the Performance of an Electrochemical Aptamer-based Tumor Necrosis Factor Alpha Sensor. 2016. M.S. thesis, University of Nebraska.


A THESIS Presented to the Faculty of The Graduate College of the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Chemistry, Under the Supervision of Professor Rebecca Y. Lai. Lincoln, Nebraska: August, 2016

Copyright (c) 2016 Miles David Mayer


In this thesis we report the design, fabrication, and comparison of three electrochemical aptamer-based biosensors decorated with different redox label locations for the detection of tumor necrosis factor alpha (TNFα). Changes in the distance of the redox label from the electrode surface and the flexibility of the aptamer are implicated in the performance of these biosensors. Our results indicate that the signal response is greatly improved when the redox label is more distal to the 5’ end of the aptamer. The change in distance between the redox label and the electrode surface is greater when the placement of the redox label is in this position. The TNFα detection limits of these sensors were determined to range from 100 pM to 1 µM. The detection capabilities of these sensors were also demonstrated in various biological fluids.

Advisor: Rebecca Y. Lai