In this paper, we demonstrated the design and experimental results of the near-infrared lab-on-a-chip optical biosensor platform that monolithically integrates the MRR and the on-chip spectrometer on the silicon-on-insulator (SOI) wafer, which can eliminate the external optical spectrum analyzer for scanning the wavelength spectrum. The symmetric add-drop MRR biosensor is designed to have a free spectral range (FSR) of ∼19 nm and a bulk sensitivity of ∼73 nm/RIU; then the drop-port output resonance peaks are reconstructed from the integrated spatial-heterodyne Fourier transform spectrometer (SHFTS) with the spectral resolution of ∼3.1 nm and the bandwidth of ∼50 nm, which results in the limit of detection of 0.042 RIU.
A LATERAL FLOW-THROUGH LABEL-FREE BIOSENSOR BASED ON SILICON PHOTONICS
The optical resonances of the silicon nanopost array patterned on a silicon-on-insulator (SOI) substrate have been investigated. The fabricated device supports optical resonances in the range of 1.55 μm with a variable Q factor depending on the angle of incidence. By sealing the device on top of the nanoposts, we demonstrated a lateral flow-through label-free biosensor built on SOI. The biosensor exhibits the refractive index sensitivity of 800 nm/RIU and the femtomolar sensitivity for detection of a breast cancer biomarker (ErbB2).
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- Award ID(s):
- 1711839
- NSF-PAR ID:
- 10062947
- Date Published:
- Journal Name:
- 21st International Conference on Miniaturized Systems for Chemistry and Life Sciences October 22-26, 2017, Savannah, Georgia, USA
- Page Range / eLocation ID:
- 565 - 566
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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