Huh Yun Suk, Chung Aram J, Cordovez Bernardo, Erickson David
Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, USA.
Lab Chip. 2009 Feb 7;9(3):433-9. doi: 10.1039/b809702j. Epub 2008 Nov 12.
Here we present a novel microfluidic technique for on-chip surface enhanced Raman spectroscopy (SERS) based biomolecular detection, exploiting the use of electrokinetically active microwells. Briefly, the chip comprises of a series of microfluidic channels containing embedded microwells that, when electrically actuated, either locally attract or repulse species from solution through a combination of electrokinetic effects. We demonstrate that the approach combines the advantages of existing homogeneous (solution phase) and heterogeneous (surface phase) on-chip techniques by enabling active mixing to enhance the rate of binding between the SERS enhancers and the biomolecular targets as well as rapid concentration of the product for surface phase optical interrogation. This paper describes the chip design and fabrication procedure, experimental results illustrating the optimal conditions for our concentration and mixing processes, and a numerical analysis of the flow pattern. To demonstrate the usefulness of the device we apply it to the quantitative detection of nucleic acid sequences associated with Dengue virus serotype 2. We report a limit of detection for Dengue sequences of 30 pM and show excellent specificity against other serotypes.
在此，我们展示了一种基于片上表面增强拉曼光谱（SERS）的生物分子检测新微流控技术，该技术利用了电动活性微孔。简而言之，芯片由一系列包含嵌入式微孔的微流控通道组成，当进行电驱动时，通过电动效应的组合，这些微孔可局部吸引或排斥溶液中的物质。我们证明，该方法结合了现有的均相（溶液相）和异相（表面相）片上技术的优点，通过实现主动混合来提高SERS增强剂与生物分子靶标之间的结合速率，以及快速浓缩产物以进行表面相光学检测。本文描述了芯片设计和制造过程、说明我们的浓缩和混合过程最佳条件的实验结果，以及流型的数值分析。为了证明该装置的实用性，我们将其应用于与登革热病毒2型相关的核酸序列的定量检测。我们报告登革热序列的检测限为30 pM，并显示出对其他血清型的优异特异性。
