Surface-enhanced Raman spectroscopy of organic molecules and living cells with gold-plated black silicon

No Thumbnail Available
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This publication is imported from Aalto University research portal.
View publication in the Research portal

Other link related to publication
Date
2020-11-11
Major/Subject
Mcode
Degree programme
Language
en
Pages
14
50971-50984
Series
ACS Applied Materials and Interfaces, Volume 12, issue 45
Abstract
Black silicon (bSi) refers to an etched silicon surface comprising arrays of microcones that effectively suppress reflection from UV to near-infrared (NIR) while simultaneously enhancing the scattering and absorption of light. This makes bSi covered with a nmthin layer of plasmonic metal, i.e., gold, an attractive substrate material for sensing of bio-macromolecules and living cells using surface-enhanced Raman spectroscopy (SERS). The performed Raman measurements accompanied with finite element numerical simulation and density functional theory analysis revealed that at the 785 nm excitation wavelength, the SERS enhancement factor of the bSi/Au substrate is as high as 108 due to a combination of electromagnetic and chemical mechanisms. This finding makes the SERS-active bSi/Au substrate suitable for detecting trace amounts of organic molecules. We demonstrate the outstanding performance of this substrate by highly sensitive and specific detection of a small organic molecule of 4-mercaptobenzoic acid and living C6 rat glioma cell nucleic acids/proteins/lipids. Specifically, the bSi/Au SERS-active substrate offers a unique opportunity to investigate the living cells' malignant transformation using characteristic protein disulfide Raman bands as a marker. Our findings evidence that bSi/Au provides a pathway to the highly sensitive and selective, scalable, and low-cost substrate for lab-on-a-chip SERS biosensors that can be integrated into silicon-based photonics devices.
Description
Rinnakkaistallenne avautuu 28.10.2021 https://repository.kaust.edu.sa/handle/10754/665699
Keywords
Black silicon, DFT, Enhancement factor, Living cells, Small organic molecules, Surface-enhanced Raman spectroscopy
Other note
Citation
Golubewa , L , Karpicz , R , Matulaitiene , I , Selskis , A , Rutkauskas , D , Pushkarchuk , A , Khlopina , T , Michels , D , Lyakhov , D , Kulahava , T , Shah , A , Svirko , Y & Kuzhir , P 2020 , ' Surface-enhanced Raman spectroscopy of organic molecules and living cells with gold-plated black silicon ' , ACS Applied Materials and Interfaces , vol. 12 , no. 45 , pp. 50971-50984 . https://doi.org/10.1021/acsami.0c13570