Experimental results obtained in different laboratories world‐wide by researchers using surface‐enhanced Raman scattering (SERS) can differ significantly. We, an international team of scientists with long‐standing expertise in SERS, address this issue from our perspective by presenting considerations on reliable and quantitative SERS. The central idea of this joint effort is to highlight key parameters and pitfalls that are often encountered in the literature. To that end, we provide here a series of recommendations on: a) the characterization of solid and colloidal SERS substrates by correlative electron and optical microscopy and spectroscopy, b) on the determination of the SERS enhancement factor (EF), including suitable Raman reporter/probe molecules, and finally on c) good analytical practice. We hope that both newcomers and specialists will benefit from these recommendations to increase the inter‐laboratory comparability of experimental SERS results and further establish SERS as an analytical tool.

We here emphasize that the surface enhanced Raman scattering (SERS) intensity has to be optimized by choosing the appropriate gold nanoparticles size for two excitation wavelengths; 632.8 and 785 nm. We discuss the role of the position and of the order of the localized surface plasmon resonance (LSPR) in such optimization for both wavelengths. At 632.8 nm, the best SERS intensity is reached for a LSPR located between the excitation and Raman wavelengths whereas at 785 nm, the LSPR should be placed outside this range. The third order of LSPR is shown to have no influence on the SERS intensity.

We report on the use of soft UV nanoimprint lithography (UV-NIL) for the development of reproducible, millimeter-sized, and sensitive substrates for SERS detection. The used geometry for plasmonic nanostructures is the cylinder. Gold nanocylinders (GNCs) showed to be very sensitive and specific sensing surfaces. Indeed, we demonstrated that less than 4 ×10⁶ avidin molecules were detected and contributed to the surface-enhanced Raman scattering (SERS) signal. Thus, the soft UV-NIL technique allows to obtain quickly very sensitive substrates for SERS biosensing on surfaces of 1 mm ².

An aptamer based SERS sensor was developed to detect picomolar concentrated ochratoxin solutions using an OPLS model.

Major improvements in fabrication techniques at the nanoscale during the last two decades enable us to exploit and control nanoscale phenomena such as the localized surface plasmons (LSP) provided by metallic nanoparticles (MNP). The large enhancement of the electromagnetic field due to plasmonic effects increases drastically the response of any analyte located close to or adsorbed on MNPs, which opens ways for detection of very low concentration of analytes and sensor miniaturization. However, the efficiency of such nanosensors requires a precise control of the optical properties of the MNPs since it strongly depends on their geometrical properties. Such precision can be reached by nanolithography techniques. The parameters that govern the near field enhancement include the geometrical parameters of the MNPs (size, shape, and gap), the LSP characteristics (near field decay length and resonance position) and the excitation parameters (excitation wavelength and associated electric field polarization). Nanolithography techniques used for surface nanostructuring include optical, focused electron and ion beams, nanoimprint and nanosphere lithographies. Nanosensor fabricated lithographically exploit localized surface plasmon resonance, surface enhanced Raman scattering, and surface enhanced fluorescence.