Interferometric Biosensor Using TiO₂ Nanotube Arrays

Abstract:

TiO₂ nanotube arrays fabricated by anodic oxidation had a large surface area and high refraction index. These microstructural properties are very attractive as interferometric biosensing materials. Label free interferometric biosensor usually used nanoporous Si materials. TiO₂ nanotube arrays had more stability for wide pH range solutions. The interferometric spectrum from nanoporous layer was treated by Fast Fourier Transform and optical thickness was measured. The optical thickness was changed with the materials in nanoporous layer. To fabricate the TiO₂ nanotube arrays, anodizing time, voltage and electrolyte were optimized. The diameter and length of TiO₂ nanotube arrays were ~100 nm and ~4 µm, respectively. To observe the loading and elution of the chlorhexidine in TiO₂ nanotube in real time, the optical thickness was measured with flow cell system. In 10 wt% chlorhexidine, optical thickness change of ~125 nm was observed.

• Periodical: Applied Mechanics and Materials (Volume 864)
• Pages: 212-217
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.864.212
• Online since: April 2017
• Authors: Wan Tae Kim, Won Youl Choi*
• Keywords: Anodic Oxidation, Interferometric Biosensor, TiO₂ Nanotube Arrays

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