Most of the previous studies of cells with FTIR microscopy or imaging have been performed with embedded dry cells. Recently imaging of single cells in the aqueous environment has been made possible by the use of ultrabright synchrotron sources.  We pioneered chemical imaging of live cancer cells in the natural aqueous environment by micro ATR-FTIR spectroscopic imaging, without recourse to a synchrotron source. This approach is significant since it allowed us to monitor fine chemical and physical changes in situ with very fast acquisition time, good spatial resolution and high molecular specificity provided by FTIR imaging. This methodology could provide a convenient method for optimisation of chemotherapy approaches and drug testing in the clinic.

For FTIR imaging in transmision, we have also devloped a novel added lens approach to remove chromatic aberration, scattering and increase magnification when imaging live cells within a microfluidic device.  The lens material matches the refractive index of the windows (usually calcium fluoride), removing these optical effects and producing better quality spectra, thus reducing the need for substantial spectral post processing with correction algorithms.  To further exploit the benefits of the added lens approach, we teamed up with researchers from UCL to study biopsy samples containing Barrett's oesophagus.  This disease is a precursor to oesophageal adenocarcinoma, and early detection and treatment can increase survival rates.  Enhancing the added lens approach with mapping enables high-resolution spectroscopic images of tissues to be obtained with reduced scattering, allowing classification algorithms to function with increased performance so that tissues can be graded from non-cancerous, through low-grade dysplasic and high-grade dysplasic up to cancerous.  Our objective is to exploit these novel approaches in spectroscopic imaging to bring vibrational spectroscopic methods into the clinic as a tool to aid histopathologists.  

Key References

  • Shinzawa H., Turner B., Mizukado J., Kazarian S. G. Protein hydrations in living cell probed by Fourier transform infrared (FT-IR) spectroscopic imaging  Analyst  (2017) in press. 
  • Kazarian S. G., Chan K. L.A. ATR-FTIR spectroscopic imaging: recent advances and applications to biological systems  (Tutorial review) Analyst (2013) 138 (7), 1940 - 1951 (doi)
  • Chan K. L. A., Kazarian S. G. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) imaging of tissues and live cells Chemical Society Reviews (2016) 45, 1850-1864 (doi).
  • Kimber J. A., Foreman L.,  Turner B., Rich P., Kazarian S. G. FTIR spectroscopic imaging and mapping with correcting lenses for studies of biological cells and tissues   Faraday Discussion (2016) 187, 69-85. (doi)
  • Chan K.L.A., Kazarian S. G. Aberration-free FTIR spectroscopic imaging of live cells in microfluidic devices Analyst (2013) 138, 4040-4047, (doi)
  • Kuimova M. K., Chan K. L. A., Kazarian S. G., Imaging of Live Cancer Cells in the Natural Aqueous Environment, Applied Spectroscopy 63 (2009) 164-171.
  • Amrania, H., McCrow A. P., Matthews M. R., et al, Ultrafast infrared chemical imaging of live cells Chemical Sciences 2 (2011) 107-111 (doi)
  • Chan K.L.A., Kazarian S. G. Aberration-free FTIR spectroscopic imaging of live cells in microfluidic devices  Analyst (2013) 138, 4040-4047  (doi) (PDF)
  • Dougan J. A., Kazarian S. G. Fourier transform spectroscopic imaging of live cells Spectroscopy Europe (2013) 25(5) 6-12 (doi)(link).
  • Kazarian S. G., Chan K. L.A. ATR-FTIR spectroscopic imaging: recent advances and applications to biological systems Analyst (2013) 138 (7), 1940 - 1951 (doi)(PDF)