Robust and Reusable Waveguide-Enhanced Raman-on-a-Chip for Sensing Complex Fluids
- 1Department of Materials Science and Engineering
- 2Massachusetts Institute of Technology
- 3InSpek SAS, 73 rue Léon Bourgeois, Palaiseau, France, 91120
Abstract
Integrated photonic sensors offer a pathway toward compact chemical analysis, but their use in unprocessed complex fluids is limited by surface fouling, chemical compatibility, and the need for stable optical coupling. Here, we develop a reusable waveguide-enhanced Raman spectroscopy (WERS) platform based on chemically resilient silicon nitride waveguides and a permanently packaged fiber-to-chip interface. The sensor incorporates a spiral sensing waveguide and a robust optical input/output architecture designed to provide reproducible coupling without active alignment. Reusability was evaluated following exposure to commercial gasoline and sequential cleaning treatments. Raman signal recovery using isopropanol as a reference analyte demonstrated improved spectral performance after solvent and oxidative cleaning. As a representative application in a chemically complex matrix, the sensor was directly immersed in commercial gasoline for quantitative ethanol determination without extraction or additional sample preparation. A ratiometric signal based on the ethanol band at 885 cm-1 and a reference band at 1000 cm-1 provided a linear calibration over 10.00–21.74% v/v ethanol (R2 = 0.9323). Independent external validation across 10.00–20.00% v/v yielded 100% prediction-interval coverage, an RMSEP of 0.46% v/v, and an MAE of 0.36% v/v. These results demonstrate that chemically robust WERS with stable packaging can support reproducible, reusable Raman sensing directly in complex fuel matrices, providing a foundation for field-deployable photonic chemical analysis.
Related
- Ultrasensitive Geosmin Sensing Using Reusable SERS-Active Porous Silicon Microarray.
- Xylan-Derived N,S-Codoped Carbon Dots for Hg2+ Detection and Reusable Paper-Based Sensing
- Heterojunction engineering coupled with enzyme-like activity in a CuS/HOF photocathode for enhanced self-powered integrated chip photofuel cell sensing of neonicotinoids
- Loss-Engineered Terahertz Pixelated Metasensors for Enhanced Molecular Vibrational Fingerprint Sensing.
- Polarization-Robust and Electrically Tunable Quasi-Bound States in the Continuum in C4-Symmetric Terahertz Metasurfaces for Refractive-Index Sensing
BibTeX
@misc{almehmadi2026robust,
title = {{Robust and Reusable Waveguide-Enhanced Raman-on-a-Chip for Sensing Complex Fluids}},
author = {Lamyaa M. Almehmadi and Tushar S. Karnik and Jérôme Michon and Juejun Hu},
howpublished = {ChemRxiv},
year = {2026},
month = oct,
doi = {10.26434/chemrxiv.15010508/v1},
url = {https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010508/v1},
note = {CC BY},
}
RIS
TY - UNPB
TI - Robust and Reusable Waveguide-Enhanced Raman-on-a-Chip for Sensing Complex Fluids
AU - Lamyaa M. Almehmadi
AU - Tushar S. Karnik
AU - Jérôme Michon
AU - Juejun Hu
PY - 2026
DA - 2026/10/15
PB - ChemRxiv
DO - 10.26434/chemrxiv.15010508/v1
UR - https://chemrxiv.org/doi/full/10.26434/chemrxiv.15010508/v1
AB - Integrated photonic sensors offer a pathway toward compact chemical analysis, but their use in unprocessed complex fluids is limited by surface fouling, chemical compatibility, and the need for stable optical coupling. Here, we develop a reusable waveguide-enhanced Raman spectroscopy (WERS) platform based on chemically resilient silicon nitride waveguides and a permanently packaged fiber-to-chip interface. The sensor incorporates a spiral sensing waveguide and a robust optical input/output architecture designed to provide reproducible coupling without active alignment. Reusability was evaluated following exposure to commercial gasoline and sequential cleaning treatments. Raman signal recovery using isopropanol as a reference analyte demonstrated improved spectral performance after solvent and oxidative cleaning. As a representative application in a chemically complex matrix, the sensor was directly immersed in commercial gasoline for quantitative ethanol determination without extraction or additional sample preparation. A ratiometric signal based on the ethanol band at 885 cm-1 and a reference band at 1000 cm-1 provided a linear calibration over 10.00–21.74% v/v ethanol (R2 = 0.9323). Independent external validation across 10.00–20.00% v/v yielded 100% prediction-interval coverage, an RMSEP of 0.46% v/v, and an MAE of 0.36% v/v. These results demonstrate that chemically robust WERS with stable packaging can support reproducible, reusable Raman sensing directly in complex fuel matrices, providing a foundation for field-deployable photonic chemical analysis.
ER -