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DOE OSTI · 1185660

Superhydrophobic Analyte Concentration Utilizing Colloid-Pillar Array SERS Substrates

Wallace, Ryan A.·Charlton, Jennifer J.·Kirchner, Teresa B.·Lavrik, Nickolay V.·Datskos, Panos G.·Sepaniak, Michael J.
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Abstract

In order to detect a few molecules present in a large sample it is important to know the trace components in the medicinal and environmental sample. Surface enhanced Raman spectroscopy (SERS) is a technique that can be utilized to detect molecules at very low absolute numbers. However, detection at trace concentration levels in real samples requires properly designed delivery and detection systems. Moreover, the following work involves superhydrophobic surfaces that includes silicon pillar arrays formed by lithographic and dewetting protocols. In order to generate the necessary plasmonic substrate for SERS detection, simple and flow stable Ag colloid was added to the functionalized pillar array system via soaking. The pillars are used native and with hydrophobic modification. The pillars provide a means to concentrate analyte via superhydrophobic droplet evaporation effects. A 100-fold concentration of analyte was estimated, with a limit of detection of 2.9 10-12 M for mitoxantrone dihydrochloride. Additionally, analytes were delivered to the surface via a multiplex approach in order to demonstrate an ability to control droplet size and placement for scaled-up applications in real world applications. Finally, a concentration process involving transport and sequestration based on surface treatment selective wicking is demonstrated.

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Wallace, Ryan A., Charlton, Jennifer J., Kirchner, Teresa B., Lavrik, Nickolay V., Datskos, Panos G., Sepaniak, Michael J.. 2014-11-04. Superhydrophobic Analyte Concentration Utilizing Colloid-Pillar Array SERS Substrates. https://doi.org/10.1021/ac5033947

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