Author of

• 11905

  +

  P2.20 - Poster Session 2 - Early Detection and Screening (ID 173)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Imaging, Staging & Screening
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/29/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 11915

    +

    P2.20-010 - Raman Spectroscopy Based Breath Analysis with Potential for Lung Cancer Detection (ID 3395)

    09:30 - 09:30  |  Author(s): K.K. Chow
    • Abstract

    Background
    Lung cancer is the top cancer killer in North America and worldwide. Current lung cancer detection tools involving X-ray, CT and bronchoscopy are relatively time-consuming and costly. Breath analyses done by mass spectrometry have shown that certain endogenous volatile organic compounds (VOCs) are related to lung cancer and revealed the potential of breath analysis for lung cancer detection. But mass spectrometry is costly and has slow turnaround times. In another interesting development, electronic noses were made for breath analysis, however the signals generated from semiconductor array cannot accurately quantify nor correlate with VOCs. Raman spectroscopy is a promising candidate for breath analysis because it can offer unique fingerprint-type signals for molecular identification. Our objective is to develop a simple, cost-effective and non-invasive tool based on Raman spectroscopy for breath analysis and potentially for lung cancer screening.

    Methods
    A Raman-gas analyzer was designed and built, based on photonic technologies. We employed a hollow core-photonic crystal fibre (HC-PCF), a novel light guide that allows light to be guided in a small hollow core and it can be filled with a gaseous sample (i.e., human breath) for spectral analysis. A gas supply system was built to provide a sealed environment for the loading and unloading of gaseous samples. A 785 nm diode laser was used for Raman excitation. Stokes Raman signals generated in the hollow core of the HC-PCF were guided to the collection optics and were analyzed by a Raman spectrometer for molecular identification.

    Results
    Raman spectra have been obtained successfully from air, reference gases (hydrogen gas, oxygen gas, carbon dioxide gas), and human breath. The limit of detection of the system was found to be approximately 15 parts per million by CO~2~ concentration in the ambient air, characterized by the Raman peaks at 1286 cm[-1] and 1388 cm[-1]. This is a more than 100-fold improvement over the recently reported detection limit with a reflective capillary fibre-based Raman cell. The detection limit can be further improved by changes to the optical configurations, optimizing the interaction length of the HC-PCF and the use of sample pre-concentration method to enhance signal-to-noise ratio.

    Conclusion
    This work demonstrated a working prototype of a simple, compact, and cost-effective breath analyzer based on hollow core photonic crystal fibre and Raman spectroscopy. With further improvement in the detection sensitivity, this method can potentially be used for lung cancer screening.