Effects of the Excitation Wavelength on the SERS Spectrum

SERS is nowadays a well-established ultrasensitive technique with potential to solve many analytical problems, especially those related to biosciences. This Perspective article aims at summarizing the experimental complexities, in particular, those related to the interaction of light with the sample, that the SERS practitioner may find when acquiring a spectrum while providing a general basis for the interpretation of the obtained vibrational features. With such an idea in mind, factors related to the instrumentation, the optical enhancer, and the analyte molecule are discussed to illustrate the effects of the incident light on the absolute and relative intensity, as well as the spectral profile of the SERS spectra.