Many life science research areas are using Raman spectroscopy as a research method. Several reasons make Raman an interesting option in life sciences, e.g. due to the advantages listed below.

Advantages of Raman in life sciences

  • Sensitivity to small structural changes
  • Minimal sample preparation
  • High spatial resolution in the case of Raman microspectroscopy
  • Powerful molecular structural technique e.g. for the investigation of micro-organisms
  • Non-invasive imaging of cells and tissues within both the laboratory and clinical settings. (Non-invasive sampling capability
  • Ease with which it can be used to extract significant data from tissue and cells
  • Lack of interference from water

Disadvantages of Raman in life sciences

  • Intrinsic weak signal / the weakness of Raman process
  • Fluorescence. For instance biological samples which are typically weak Raman scatterers. Also the influence of fluorescence on Raman spectra is problematic.
  • Sensitivity of samples. For instance cellular material is typically quite fragile and thus samples can be easily damaged by higher laser energies

TimeGated® Advantages for Life Sciences

(examples, more to come)

• Effective Fluorescence suppression makes measuring many samples impossible for traditional CW Raman possible.
• Timegated® pulsed laser is more gentle in some cases to delicate samples types than traditional CW Raman.
• Sample Status Screening –window. Timegated® is able to follow the status of the sample during the measurement.

TimeGated ® technique has been tested e.g. in areas described below

Medicine

Raman spectroscopy has many features that are useful for medical diagnostics. The high chemical specificity, minimal or lack of sample preparation and the ability to use advanced optical technologies are just a few of them. Recent efforts have developed Raman spectroscopy to the point where the diagnostic accuracy and speed are compatible with clinical use. We believe Timegated® could bring something new into these efforts.

Raman spectroscopy was used to study chemical structure of human articular cartilage samples. See the comparison results of equivalent laser excitation 532 CW Raman below and the Timegated® results. The researcher’s comment on the results:

“Timegated® device works better than the comparisson device XX when measuring few millimeter thick dry articular cartilage tissue samples. Timegated® device detects e.g. collagen peaks at 1670 and 1450 cm-1, where the comparisson device XX shows strong fluorescence.”

Click the pics to get a better view on the spectra.

Biology

Raman spectroscopy has emerged as a powerful technique in the study of various chemical processes in biology. This technique is non-invasive, label-free, capable of providing molecular identity and can be performed in robust conditions.

Raman spectroscopy has been used for years to identify a particular genus in a group of algae. As each biomolecule has its own signature Raman spectrum, this characteristic signal can be used to identify and characterize the biomolecules in algae. Raman spectrum can be used to identify the components, determine the molecular structure and various properties of biomolecules in algae. As an example measured by Timegated® we present Chlorella vulgaris algae. The peaks are mainly due to beta-carotene present in this alga.

References
Kong, K., Kendall, C., Stone, N., & Notingher, I. (2015). Raman spectroscopy for medical diagnostics – From in-vitro biofluid assays to in-vivo cancer detection. Advanced Drug Delivery Reviews, 89, 121134.
Kundu, P. P., & Narayana, C. (2012). Raman Based Imaging in Biological Application – A Perspective. Journal of Medical & Allied Sciences, 2(2), 4148.
Tomar, V. (2012). Raman Spectroscopy of Algae: A Review. Journal of Nanomedicine & Nanotechnology, 03(02).
Baena, J. R., & Lendl, B. (2004). Raman spectroscopy in chemical bioanalysis. Current Opinion in Chemical Biology, 8(5), 534539.
Harz, M., Rösch, P., & Popp, J. (2009). Vibrational spectroscopy-A powerful tool for the rapid identification of microbial cells at the single-cell level. Cytometry Part A, 75(2), 104113.
Butler, H. J., Fogarty, S. W., Kerns, J. G., Martin-Hirsch, P. L., Fullwood, N. J., & Martin, F. L. (2015). Gold nanoparticles as a substrate in bio-analytical near-infrared surface-enhanced Raman spectroscopy. The Analyst, 140(9), 30907.