Spatially offset Raman spectroscopy: a new perspective for heritage science

Spatially Offset Raman Spectroscopy (SORS) has emerged as an effective non-invasive tool in heritage science. By enabling the study of subsurface layers, SORS overcomes limitations of traditional Raman spectroscopy (constrained often to near-surface analysis). In this study we describe how, by using handheld SORS device combined with multivariate analysis, it is possible to non-invasive characterize the preservation fluids in historical natural history collections, enabling the identification of chemical components (i.e. different alcohols in water such as glycerol, ethanol, methanol, and formaldehyde) and differentiation of fluid types and concentrations through original glass containers.