New Article in ACS AM&I

posted Sep 25, 2017, 4:48 PM by Shin-Hyun Kim
Hyelim Kang, Yong Joon Heo, Dong Jae Kim, Ju Hyeon Kim, Tae Yoon Jeon, Soojeong Cho, Hye-Mi So, Won Seok Chang, and Shin-Hyun Kim, "Droplet-Guiding Superhydrophobic Arrays of Plasmonic Microposts for Molecular Concentration and Detection", ACS Applied Materials & Interfaces Accepted for publication (2017).  (Corresponding author) [pdf]

Droplet-guiding superhydrophobic SERS substrates are created by a combinatorial lithographic technique. Photolithography defines the pattern of a micropillar array with a radial density gradient, whereas colloidal lithography features a nanotip array on the top surface of each micropillar. The nanotip array renders the surface superhydrophobic and the pattern of micropillars endows the radial gradient of contact angle, enabling the spontaneous droplet migration toward the center of the pattern. Water droplets containing target molecules are guided to the center and the molecules dissolved in the droplets are concentrated at the surface of the central micropillar during droplet evaporation. Therefore, the molecules can be analyzed at the predefined position by Raman spectra without scanning the entire substrate. At the same time, SERS-active nanotip array provides high sensitivity of Raman measurement.