. 2017 May 15;2:12. doi: 10.1038/s41536-017-0014-3

Table 1.

Summary of Raman spectroscopy techniques

Raman technique	Brief description	Advantages	Applications in biomedicine
Spontaneous Raman spectroscopy	Detects intrinsic Raman scattering of molecules. Can be combined with fibre probes or microscopy to give spatial and biochemical information	Label free, non-invasive and non-destructive, no sample preparation required	Diagnostics, guided surgery,^{53, 54} molecular pathology,^{82, 83, 97} stem cell research,^{24, 65, 67–69, 98} tissue engineering^70–73
RRS	Particular bands enhanced by matching the excitation wavelength with electronic resonance of molecules, can be coupled with SERS	10³–10⁵-fold increase in signal-to-noise, chromophores can be investigated	Characterising specific biomolecules e.g., carotenoids, cytochrome^{25, 26, 99}
SERS	Raman signal is enhanced using roughened metal surface e.g., nanoparticles, metal coated slide	10⁶-fold increase in signal-to-noise, functionalised nanoparticles	pH and redox measurements,^{33, 34} cell-based assays,^{100, 101} immunoassays¹⁰²
SORS	Raman signal measured at site offset from point of excitation, to collect diffusely scattered photons	Allows greater penetration into sample, more depth information in thicker tissues	Potential detection of calcifications and cancer margins in breast tissue^{41, 43}
SRS/CARS	Non-linear variants requiring pulsed, synchronised laser source.	Video rate, label free biomolecular imaging, 5× increase in signal-to-noise	Imaging specific molecules of interest e.g., hydroxyapatite, lipids, drugs^{47, 62, 84}