Surface-Enhanced Raman Scattering (SERS) is a very interesting technique for the detection of analytes at ultra-low concentrations. In recent years, it has been applied to the detection of species with biological or medical interest [1]. However, one of the key issues of SERS-based assays is the low reproducibility between different substrates and measurements due to the low control of hot spots and the strong influence of the surface features on the SERS activity. Therefore, there is a strong scientific interest for increasing the applicability of SERS assays for quantitative studies with reproducible and simple methods. Electrochemically roughened electrodes have been widely employed for SERS-based assays. Recently, we have demonstrated that the utilization of screen-printed electrodes with in situ dynamic simultaneous roughening and detection could improve the precision of these assays [2]. Furthermore, the dynamic and in situ electrogeneration of SERS substrates allows to obtain a strongly active metallic surface for increasing detection sensitivity. Screen-printed electrodes due to their versatility, precise mass-fabrication, disposability and low-cost could be promising SERS substrates.

In this work, the evaluation of electrochemical SERS (EC-SERS) for the detection of biologically-related species at very low concentrations is performed using metallic screen-printed electrodes. Several species with a possible biological interest were tested such as Ruthenium-bipyridine, Naratriptan or Nicotinamide. Ruthenium-bipyridine is a very interesting molecule because it is the most common detection label in electrochemiluminescence bioassays due to its exceptional performance and sensitivity. Naratriptan is a pharmaceutical active ingredient used for the treatment of migraine headaches in human beings. Nicotinamide is an essential B-vitamin necessary to support the function of many biological enzymes. EC-SERS using screen-printed electrodes allows the detection of these species at very low concentrations.

[1] L.A. Lane, X. Qian, S. Nie, “SERS Nanoparticles in Medicine: From Label-Free Detection to Spectroscopic Tagging”, Chem. Rev. 115 (2015), 10489-10529.

[2] D. Martín-Yerga, A. Pérez-Junquera, M.B. González-García, J.V. Perales, A. Heras, A. Colina, D. Hernández-Santos, P. Fanjul-Bolado, “Quantitative Raman Spectroelectrochemistry using silver screen-printed electrodes”, Electrochim. Acta 264 (2018), 183-190.