Silicon based microfluidic cell for terahertz frequencies
| Autor: | Adam J. Baragwanath, Andrew J. Gallant, G. P. Swift, DeChang Dai, J.M. Chamberlain |
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| Rok vydání: | 2010 |
| Předmět: |
Silicon
Aqueous solution Materials science Terahertz radiation Microfluidics Terahertz waves Analytical chemistry General Physics and Astronomy chemistry.chemical_element Microwave generation Elemental semiconductors Dielectric Primary alcohol Time-domain reflectometry Optical path chemistry Microwave spectroscopy Spectroscopy |
| Zdroj: | Journal of applied physics, 2010, Vol.108(1), pp.013102 [Peer Reviewed Journal] |
| Popis: | We present a detailed analysis of the design, fabrication and testing of a silicon based, microfluidic cell, for transmission terahertz time-domain spectroscopy. The sensitivity of the device is tested through a range of experiments involving primary alcohol/water mixtures. The dielectric properties of these solutions are subsequently extracted using a Nelder–Mead search algorithm, and are in good agreement with literature values obtained via alternative techniques. Quantities in the order of 2 μmol can be easily distinguished for primary alcohols in solution, even with the subwavelength optical path lengths used. A further display of the device sensitivity is shown through the analysis of commercial whiskeys, where there are clear, detectable differences between samples. Slight absorption variations were identified between samples of the same commercial brand, owing to a 2.5% difference in their alcoholic content. Results from data taken on subsequent days after system realignment are also presented, confirming the robustness of the technique, and the data extraction algorithm used. One final experiment, showing the possible use of this device to analyze aqueous biological samples is detailed; where biotin, a molecule known for its specific terahertz absorptions, is analyzed in solution. The device sensitivity is once again displayed, where quantities of 3 nmol can be clearly detected between samples. |
| Databáze: | OpenAIRE |
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