Cardiovascular Risk Stratification on the Basis of Surface Enhanced Raman Spectroscopy

Spectral measurements of blood serum were performed on a silver nanoparticle substrate. Serum samples were collected and placed in sterile tubes with subsequent freezing at -18°C. Immediately before analysis, samples were thawed at room temperature. For spectral analysis, each 1.5 μL serum sample was applied to a substrate with a layer of silver nanoparticles and dried for 30 minutes. The spectral characteristics of serum were analyzed using an experimental bench consisting of a spectrometric system and a microscope (ADF U300, ADF, China). The spectra were excited in the near infrared range using a laser module with a center wavelength of 785 nm. Each of the obtained spectra represented a discrete set of 1700 parameters in the range of studied frequencies.