SHINERS in cultural heritage: Can SHINERS spectra always be compared with normal Raman spectra? A study of alizarin and its adsorption in the silicon dioxide shell

Raman microspectroscopy is a powerful analytical technique in cultural heritage. However, results are often compromised by luminescence interference and poor sensitivity. Surface-enhanced spectroscopy (SERS) an alternative that can enhance the signal quench luminescence, but interaction of analyte metal substrate produces altered spectra. Shell-isolated nanoparticle-enhanced (SHINERS) promising modification SERS encases nanoparticles ultrathin inert shells. As consequence, it reported SHINERS spectra be directly compared with normal spectra, this not always case, as discussed work. SHINERS, SERS, were obtained from alizarin. The resulting showed data comparable spectrum alizarin adsorbed silica, isolated structure silica discussed. Luminescence quenching observed attributed both to LSPR metallic nanoparticle cores alizarin–silica shell chemisorption. Both silica-encapsulated silver gold considered, shown dependent on rather than specific core within, contrast our observations Ag Au nanoparticles. agnostic quality potential advantage for collection comparison reference data. Additionally, systems result quite stable pHs ranging from, at least, 6.0 9.3. Future research directions heritage also