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Tailoring of Nanotextured Zinc Oxide Thin Films for Enhanced Biosensing

Published online by Cambridge University Press:  21 August 2014

Michael Jacobs
Affiliation:
Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, EC 39, Richardson, TX 75080, U.S.A.
Rujuta Munje
Affiliation:
Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, EC 39, Richardson, TX 75080, U.S.A.
Bilal Quadri
Affiliation:
Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, EC 39, Richardson, TX 75080, U.S.A.
Sriram Muthukumar
Affiliation:
Department of Materials Science and Engineering, University of Texas at Dallas, 800 W. Campbell Road, EC 39, Richardson, TX 75080, U.S.A.
Shalini Prasad
Affiliation:
Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, EC 39, Richardson, TX 75080, U.S.A.
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Abstract

This study demonstrates the development of a zinc oxide (ZnO) based microelectrode sensor for the ultra-sensitive detection of protein biomarkers. Our research focuses on utilizing a materials-based approach to achieve this objective by utilizing ZnO as part of our biosensor for (1) improved surface binding to enhance sensitivity and (2) creating a nanotextured surface for enhanced output signal response. Nanotextured ZnO thin films were integrated onto printed circuit boards using RF magnetron sputter deposition. Films sputtered with and without the presence of oxygen were examined for possible differences in biosensor efficacy. These fabrication conditions not only dictate the number of oxygen vacancies within the film but also regulate the amount of zinc and oxygen terminated ends occurring on the material surface. The correlation between the surface terminations of the nanotextured ZnO to its performance as a biosensor was evaluated using two cross-linker molecules, dithiobis succinimidyl propionate and (3-aminopropyl)triethoxysilane, that maintain different binding chemistries to ZnO. Qualitative and quantitative assessment of cross-linker binding was accomplished using fluorescent microscopy and fluorescent intensity measurements. Electrical impedance spectroscopy (EIS) was used as the transduction mechanism for detection of the well-established cardiac biomarker, troponin-T. Utilizing EIS with a functionalized immunoassay on the ZnO surface, troponin-T was detected as low as 10 fg/mL using ZnO films sputtered without oxygen. This enhanced detection of the cardiac biomarker can be directly attributed to 1) oxygen vacancies within the metal oxide film, 2) the nanotexturing of the sensing site surface, and 3) the ability to bind a significant amount of cross-linker molecules for immobilizing capture antibodies.

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Articles
Copyright
Copyright © Materials Research Society 2014 

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References

REFERENCES

Zhang, X., et al. . Electrochemical Sensors, Biosensors and their Biomedical Applications, Elsevier Science, 2011.Google Scholar
Daniels, J. S. and Pourmand, N.. Electroanalysis, vol. 19, p. 12391257, 2007.CrossRefGoogle Scholar
Bogomolova, A., et al. . Analytical Chemistry, vol. 81, p. 39443949, 2009.Google Scholar
Gaikwad, R.S., et al. . Sensors and Actuators A: Physical, vol. 189, p. 339, 2013.CrossRefGoogle Scholar
Huang, J., et al. . MRS Proceedings, vol. 1287, p. mrsf10-1287-f08-05, 2011.CrossRefGoogle Scholar
Jagadish, C. and Pearton, S.J.. Zinc Oxide Bulk, Thin Films and Nanostructures: Processing, Properties, and Applications, Elsevier Science, 2011.Google Scholar
Sunandan, B., et al. . Science and Technology of Adv. Materials, vol. 10, p.13001, 2009.Google Scholar
Sadik, P.W., et al. . Journal of Applied Physics, vol. 101(10), p. 104514–5, 2007.Google Scholar
Grasset, F., et al. . Journal of Alloys and Compounds, vol. 360(12), p. 298311, 2003.Google Scholar
Hamilton, N.. Traffic, vol. 10(8), 951961, 2009.Google Scholar
Hong, H., et al. . Nano Letters, vol. 11(9), p. 37443750, 2011.Google Scholar
Panneer Selvam, A., et al. . EMBC, 2012 Annual International Conference of the IEEE. p.32513254, 2012.Google Scholar
Jacobs, M., et al. . Biosensors and Bioelectronics, vol. 55, p. 713, 2014.CrossRefGoogle Scholar