Sub-wavelength plasmonic readout for direct linear analysis of optically tagged DNA
Name
Varsanik-2010-Sub-wavelength plasmonic.pdf
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9.64 MB
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Adobe PDF
Checksum (MD5)
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Author(s)
Varsanik, Jonathan S.
Teynor, William
LeBlanc, John
Clark, Heather A.
Krogmeier, Jeffrey
Yang, Tian
Crozier, Kenneth
Bernstein, Jonathan
Date Issued
February 2010
Journal
Proceedings of SPIE--the International Society for Optical Engineering, v. 7577
Publisher
SPIE
Citation
Varsanik, Jonathan et al. “Sub-wavelength plasmonic readout for direct linear analysis of optically tagged DNA.” Plasmonics in Biology and Medicine VII. Ed. Tuan Vo-Dinh & Joseph R. Lakowicz. ©2010 SPIE
Version
Final published version
Abstract
This work describes the development and fabrication of a novel nanofluidic flow-through sensing chip that utilizes a plasmonic resonator to excite fluorescent tags with sub-wavelength resolution. We cover the design of the microfluidic chip and simulation of the plasmonic resonator using Finite Difference Time Domain (FDTD) software. The fabrication methods are presented, with testing procedures and preliminary results. This research is aimed at improving the resolution limits of the Direct Linear Analysis (DLA) technique developed by US Genomics [1]. In DLA, intercalating dyes which tag a specific 8 base-pair sequence are inserted in a DNA sample. This sample is pumped though a nano-fluidic channel, where it is stretched into a linear geometry and interrogated with light which excites the fluorescent tags. The resulting sequence of optical pulses produces a characteristic "fingerprint" of the sample which uniquely identifies any sample of DNA. Plasmonic confinement of light to a 100 nm wide metallic nano-stripe enables resolution of a higher tag density compared to free space optics. Prototype devices have been fabricated and are being tested with fluorophore solutions and tagged DNA. Preliminary results show evanescent coupling to the plasmonic resonator is occurring with 0.1 micron resolution, however light scattering limits the S/N of the detector. Two methods to reduce scattered light are presented: index matching and curved waveguides.
Subjects
Plasmon resonance
Optical waveguide
Microfluidics
Sub-wavelength resolution
MIT Department
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1117/12.841165
