Back to Search
Start Over
Enhancing Raman signals from bacteria using dielectrophoretic force between conductive lensed fiber and black silicon
- Source :
- Biosensors and Bioelectronics. 191:113463
- Publication Year :
- 2021
- Publisher :
- Elsevier BV, 2021.
-
Abstract
- An osmium-coated lensed fiber (OLF) probe combined with a silver-coated black silicon (SBS) substrate was used to generate a dielectrophoretic (DEP) force that traps bacteria and enables Raman signal detection from bacteria. The lensed fiber coated with a 2-nm osmium layer was used as an electrode for the DEP force and also as a lens to excite Raman signals. The black silicon coated with a 150-nm silver layer was used both as the surface-enhanced Raman scattering (SERS) substrate and the counter electrode. The enhanced Raman signal was collected by the same OLF probe and further analyzed with a spectrometer. For Raman measurements, a drop of bacterial suspension was placed between the OLF probe and the SBS substrate. By controlling the frequency of an AC voltage on the OLF probe and SBS substrate, a DEP force at 1 MHz concentrated bacteria on the SBS surface and removed the unbound micro-objects in the solution at 1 kHz. A bacteria concentration of 6 × 104 CFU/mL (colony forming units per mL) could be identified in less than 15 min, using a volume of only 1 μL, by recording the variation of the Raman peak at 740 cm−1.
- Subjects :
- Silicon
Auxiliary electrode
Materials science
Biomedical Engineering
Biophysics
Biosensing Techniques
02 engineering and technology
Substrate (electronics)
Spectrum Analysis, Raman
01 natural sciences
Signal
chemistry.chemical_compound
symbols.namesake
Electrochemistry
Bacteria
business.industry
010401 analytical chemistry
Black silicon
General Medicine
021001 nanoscience & nanotechnology
0104 chemical sciences
chemistry
Electrode
symbols
Optoelectronics
0210 nano-technology
business
Raman spectroscopy
Layer (electronics)
Raman scattering
Biotechnology
Subjects
Details
- ISSN :
- 09565663
- Volume :
- 191
- Database :
- OpenAIRE
- Journal :
- Biosensors and Bioelectronics
- Accession number :
- edsair.doi.dedup.....e9edca4bdebb94bad54754c7de1ecee1