Estudio de los factores determinantes para el desarrollo de sensores SERS efectivos y económicos

Nanotechnology has provided endless tools to improve detection systems in the most diverse fields of science. One of those tools is the development of surface enhanced Raman spectroscopy (SERS) that promotes the amplification in 8-10 orders of magnitude of the Raman signals obtained by conventional methods. However, the success of this analytical technique depends on many factors such as the core material of the nanoparticles, their morphology and the adsorption pattern of the analytes on the metal surface, aspects that are not always considered when designing this type of sensors. This work has focus on the effect of these features using a reference molecule such as methylene blue (MB) and two coffee metabolites, trigonelline and chlorogenic acids (CGAs), known as potential quality markers of this agricultural product so important in Peru. Herein, we reported higher Raman signals when using silver nanostructures over their gold homologues, and nanotriangles show better results than nanospheres of the same material, due to the non-homogeneous distribution of the electromagnetic field described for anisotropic structures. Lastly, when the two coffee metabolites were evaluated, only one of them induced an increase of its respective signals, which proves the great influence of the interaction between the analysed molecule and the metal, as the adsorption may hinder some of its vibrational modes, diminishing its applicability.