Raman spectroscopy applications for the diagnosis and follow-up of type 2 diabetes mellitus. A brief review

Background: There is considerable interest in developing faster, less invasive, and more objective techniques to diagnose type 2 diabetes mellits (T2DM). Optical techniques like Raman spectroscopy and surface-enhanced Raman spectroscopy (SERS) are efficient, precise, low-cost, portable, and easy to handle, which seem to overcome most of the present difficulties of actual tests for T2DM diagnosis. However, the use of both Raman spectroscopy and surface-enhanced Raman spectroscopy (SERS) has been limited for T2DM diagnosis or follow-up. Objective: To gather information regarding the use of Raman spectroscopy and SERS to evaluate the spectra of biofluids (blood components, saliva, and urine) and tissues (skin) as an early diagnostic tool or follow-up for T2DM. Results: Skin and biofluids provide a great amount of information that can be analyzed by Raman spectroscopy and SERS. These optical techniques are excellent for clinical applications and can differentiate people with T2DM from healthy individuals, predict complications arising from T2DM (chronic kidney disease), and might be used to monitor glucose (glycemic control). Conclusion: Raman spectroscopy and SERS are good optical techniques for the diagnosis of T2DM in which sample preparation is not necessary or very simple, non-destructive, non-invasive, relatively fast to acquire, and low-cost.