TY - JOUR
T1 - Facile fabrication of plasmonic wettability contrast paper surface for droplet array-based SERS sensing
AU - Peethan, Alina
AU - Aravind, M.
AU - Unnikrishnan, V. K.
AU - Chidangil, Santhosh
AU - George, Sajan D.
N1 - Funding Information:
We gratefully acknowledge financial support from the Manipal Academy of Higher Education, FIST program of the Government of India (SR/FST/PSI-174/2012) and the Department of Science and Technology, Government of India (IDP/BDTD/ 20/2019).
Funding Information:
We gratefully acknowledge financial support from the Manipal Academy of Higher Education , FIST program of the Government of India ( SR/FST/PSI-174/2012 ) and the Department of Science and Technology , Government of India ( IDP/BDTD/ 20/2019 ).
Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2022/1/1
Y1 - 2022/1/1
N2 - A facile and cost-effective method was developed to create superhydrophobic surfaces onto a superhydrophilic commercial paper for the application of droplet splitting of microliter droplets into nano and sub-nano-liter droplets. The high wettability contrast of nearly 180° between the superhydrophobic region created via candle soot coated onto the patterned poly (dimethylsiloxane) and the paper causes the self-partitioning of a 1 µl droplet while sliding through the surface with a speed ranging from 0.001 to 7.3 mm/s. Additionally, the splitting of the droplet demonstrated for µl droplets of surface tension ranging from 72 mN/m to 38.5 mN/m. The plasmonic droplet assay for surface-enhanced Raman spectroscopy was fabricated via in-situ reduction of Ag nanoparticles onto the superhydrophilic region. The Raman scattering studies of methyl orange using the prepared substrates exhibit a limit of detection of 670 pM. Further, by using methyl orange as a probe molecule, selective detection of Hg2+ ions up to a concentration of 100 pM in nanoliter droplet volume is demonstrated. It is envisaged that these cost-effective plasmonic nanoliter droplet assays created via patterned superhydrophilic-superhydrophobic can find applications in high throughput screening, microfluidic bioassays, medical diagnosis.
AB - A facile and cost-effective method was developed to create superhydrophobic surfaces onto a superhydrophilic commercial paper for the application of droplet splitting of microliter droplets into nano and sub-nano-liter droplets. The high wettability contrast of nearly 180° between the superhydrophobic region created via candle soot coated onto the patterned poly (dimethylsiloxane) and the paper causes the self-partitioning of a 1 µl droplet while sliding through the surface with a speed ranging from 0.001 to 7.3 mm/s. Additionally, the splitting of the droplet demonstrated for µl droplets of surface tension ranging from 72 mN/m to 38.5 mN/m. The plasmonic droplet assay for surface-enhanced Raman spectroscopy was fabricated via in-situ reduction of Ag nanoparticles onto the superhydrophilic region. The Raman scattering studies of methyl orange using the prepared substrates exhibit a limit of detection of 670 pM. Further, by using methyl orange as a probe molecule, selective detection of Hg2+ ions up to a concentration of 100 pM in nanoliter droplet volume is demonstrated. It is envisaged that these cost-effective plasmonic nanoliter droplet assays created via patterned superhydrophilic-superhydrophobic can find applications in high throughput screening, microfluidic bioassays, medical diagnosis.
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U2 - 10.1016/j.apsusc.2021.151188
DO - 10.1016/j.apsusc.2021.151188
M3 - Article
AN - SCOPUS:85115781686
SN - 0169-4332
VL - 571
JO - Applied Surface Science
JF - Applied Surface Science
M1 - 151188
ER -