Vibrational Biospectroscopy in the Clinical Setting: Exploring the Impact of New Advances in the Field of Immunology

Table 2

FTIR vs Raman spectroscopy: advantages and disadvantages.

Technique	Advantages	Disadvantages
FTIR	(i) High sensitivity and speed; (ii) No labels, minimal sample preparation; (iii) Enable all frequency that measures metabolites simultaneously; (iv) Nondestructive	(i) Constraints on sample thickness and uniformity; (ii) Interference from water; (iii) Complex mixtures can lead to misleading spectra; (iv) Limited to IR-active molecule (with dipole moment)
Raman	(i) Minimal sample preparation and setup; (ii) Minimal interference from water; (iii) Can be used for analysis of all molecules; (iv) Suitable on any surface; (v) Little-to-no sample preparation; (vi) Can be nondestructive (when used with low power lasers or short exposure times)	(i) Autofluorescence may interfere with the ability of taking Raman spectra in biological samples; (ii) Sophisticated data analysis; (iii) Weak Raman signal can lead to long acquisition times; (iv) Initial setup cost and instrumentation can be costly; (v) Destructive–biological samples can be sensitive to high power laser and extended exposure times
SERS	(i) Higher sensitivity; (ii) Minimal sensitivity to water; (iii) Highly specific; (iv) Multiplexing capability; (v) Faster results	(i) Higher cost; (ii) Background signal from interference; (iii) Intricate sample preparation; (iv) Poor measurement reproducibility
NIRS	(i) No sample preparation; (ii) Low cost per sample: no solvents needed; (iii) Rapid analysis; (iv) Versatile; (v) Faster results	(i) Low sensitivity due to lower absorption coefficients; (ii) Complex data interpretation; (iii) Environmental factors (like temperature and humidity) can affect the accuracy and reproducibility of measurements; (iv) Indirect method hence a development of multivariate calibration model required