We present the first validation and application of portable Sequentially Shifted Excitation (SSE) Raman spectroscopy for the survey of painted layers in art. The method enables the acquisition of shifted Raman spectra and the recovery of the spectral data through the application of a suitable reconstruction algorithm. The technique has a great potentiality in art where commonly a strong fluorescence obscures the Raman signal of the target, especially when conventional portable Raman spectrometers are used for in situ analyses. Firstly, the analytical capability of portable SSE Raman spectroscopy is critically discussed using reference materials and laboratory specimens, comparing its results with other conventional high performance laboratory instruments (benchtop FT-Raman and dispersive Raman spectrometers with an external fiber optic probe); secondly, it is applied directly in situ to study the complex polychromy of Italian prestigious terracotta sculptures of the 16(th) century. Portable SSE Raman spectroscopy represents a new investigation modality in art, expanding the portfolio of non-invasive, chemically specific analytical tools.

ZnO micro and nanorods, produced through simple and inexpensive techniques, resulted to be strong antimicrobials against Gram-positive bacteria, in vitro as well as in vivo, by altering cell outer structures like membrane and exopolysaccharides.

Cultural detective work: Remote hyperspectral imaging in the mid‐infrared region enables the identification and localization of the painting materials used by artists (see brightness temperature difference image overlayed with the corresponding portion of the painting Sestante 10 by Alberto Burri and IR reflection spectra for this area). The resulting molecular images are thus of great value for art conservation.

Cultural detective work: Remote hyperspectral imaging in the mid‐infrared region enables the identification and localization of the painting materials used by artists (see brightness temperature difference image overlayed with the corresponding portion of the painting Sestante 10 by Alberto Burri and IR reflection spectra for this area). The resulting molecular images are thus of great value for art conservation.

No abstract

No abstract

Abstract The relevance of FT-IR spectroscopy in heritage science has experienced a constant grow in the last two decades owing to analytical peculiarities that make it an extremely useful tool to answer the questions posed by the study and conservation of art-historical and archaeological materials. High versatility, sensitivity and molecular specificity are, in fact, all requirements that FT-IR spectroscopy fulfils allowing for the investigation of the chemical properties of heritage materials spanning from the micro- to the macro-scale and offering a variety of approaches to minimize sample manipulation and maximize extracted information. Molecular identification and localisation at high lateral resolution of organic and inorganic components in micro-samples was, over recently, the mostly exploited use of FT-IR in heritage science; however, benefiting from technological progress and advances in optical materials and components achieved in the last decade, it now stands out also for non-invasive surface analysis of artworks by fully portable instrumentation.

This paper is aimed at demonstrating the potentiality of high resolution Attenuated Total Reflection Fourier Transform Infrared micro-mapping (micro-ATR-FTIR) to reconstruct the images of micrometric multi-layered systems. This method can be an effective analytical alternative when the layer thickness requires high lateral resolution, and fluorescence or thermal effects prevent the deployment of conventional analytical techniques such as micro-Raman spectroscopy. This study demonstrates the high micro-ATR-FTIR setup performances in terms of lateral resolution, spectral quality and chemical image contrast using a new laboratory instrument equipped with a single element detector. The method has been first validated on mock-ups and then successfully applied on cross-sectional samples from real artworks: Leonardo da Vinci's mural painting, characterised by a few micrometers thin sequence of organic and inorganic layers, and an outdoor marble statue, with a complex sequence of decay products on its surface. This study paves the way to a new investigation modality of micrometric systems, combining high lateral resolution with excellent spectral quality, essential in the field of Cultural Heritage as well as in the wider area of materials and forensic sciences.