Surface enhanced Raman spectroscopy (SERS) was utilised for detection of organic pigments and dyes of cultural heritage samples. For that purpose, substrates based on silver nanoparticles were prepared and characterised. Also, a new viscous UV-photoreduced substrate was prepared. Hydroxyproply cellulose was used as a stabiliser, thus possible precipitation of the silver was avoided. Their SERS-activity was tested with alizarin as a probe molecule. Furthermore, substrates enabled the detection of synthetic organic pigment Alizarin Crimson dark (alizarin), organic dye Alizarin Carmine (Alizarin Red S, sodium alizarinsulfonate) and organic lake pigment Madder Lake violet (purpurin, alizarin). Latter two were also detected in colour layers prepared with different organic binders. Analysis was successful with no interfering signal of other organic compounds; therefore it was shown that no pre-treatment of the sample is needed prior analysis. Based on these results, it was established that new UV-photoreduced substrate among prepared substrates shows optimal characteristics for analysis of cultural heritage samples. Additionally, it was possible to detect organic pigment on cross section of the sample taken from the model painting prepared according to Baroque painting techniques.
D.10 Educational activities
COBISS.SI-ID: 36165125The large altarpiece of St. Nicholas is one of Tintoretto's late works and it was painted for the former chapter house, today’s cathedral in Novo mesto. Like the majority of the artist's work, the painting of St Nicholas is not signed or dated. Since the 19th century the painting has undergone a series of restoration treatments, which considerably changed its appearance. The contribution at the conference presents the professional work (scientific research and conservation-restoration treatments), which has been carried out on the painting in recent years.
F.27 Contribution to preserving/protecting natural and cultural heritage
COBISS.SI-ID: 512725035Non invasive reflection FTIR measurements provide valuable information about the chemical composition and degradation processes of the surface of works of art which is of a great importance in designing safe conservation-restoration interventions. However, band assignments and the identification of components can often be complicated by the fact that the IR reflection response of artworks’ surface is rather complex. A novel approach of µ-transflection analysis of artworks’ surface is presented, the technique that gives the opportunity to overcome the problems. In addition to the identification of the components present at the surface of the work of art, the technique can also be applied for monitoring of the chemical cleaning during the restoration processes. Some examples of the identification of the surface of a Baroque easel painting are presented.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 512789035