Microchemistry and Microscopy Art Diagnostic Laboratory (M2ADL)

Description

The M2ADL laboratory operates in the field of chemistry applied to cultural heritage. The research lines currently undertaken deal with the development of innovative analytical methodologies for the characterization and localization of organic and inorganic compounds in objects of artistic and archaeological interest. Advanced non-invasive and micro-destructive spectroscopic techniques are used for this purpose, assisted by the chemometric analysis of the data. The ultimate aim of the proposed approaches is the study of alteration phenomena, the study of materials and execution techniques, the identifications of physico-chemical interactions originating the degradation processes and the evaluation of the effectiveness of new materials for restoration.

Instrumentation

  • Stereomicroscope Leica MZ6

  • Optical Microscope Olympus BX51M (visible light, fluorescence light) with objectives (5x, 10x, 20x, 50x, 100x)

    The microscopic analysis allows to obtain morphological information on the surface of an artwork. If the analysis refers to micro-samples, it is possible to observe and reconstruct the sequence of the different layers that constitutes the artwork (stratigraphic analysis)

  • Benchtop infrared spectrometer NICOLET 5700 FT-IR, Thermo Nicolet, with accessories

  • Benchtop infrared spectrometer AVATAR 370 FT-IR, Thermo Nicolet, with accessories

  • Portable infrared spectrometer Cary 630 FT-IR, Agilent Technologies, with accessories

    Infrared analysis is a molecular technique that allows the characterization of organic and inorganic substances in the analyzed artwork. By means of this technique it is possible to identify binders, adhesives, paints, pigments and dyes. The most common method of analysis, in transmission (micro-destructive), involves the preparation and analysis of KBr tablets (100 mg) in which a minimum quantity of sample from the object (about 1 mg) is added. A second method of analysis is the total attenuated reflection mode (ATR), which allows the analysis of the sample as it is without any preparation procedure. In this case the analysis is achieved through the direct contact between the sample and the ATR probe (MacroATR). The total reflection mode (non-invasive) allows to perform the infrared analysis directly on the surface of interest, without any alteration of the area under examination. Among the above-mentioned infrared instruments the Nicolet 5700 and AVATAR 370 spectrometers can operate both in transmission and ATR (MacroATR) mode, while the Cary 630 spectrometer is used for total reflection analysis.

  • X-ray Fluorescence (XRF) Artax, Bruker

    The XRF technique, by exploiting X-rays, provides the elemental composition of the examined artifact. The instrument is used for the characterization of the inorganic component of art objects such as metals, metal alloys, pigments and ceramic materials.

  • Multispecral imaging scanner ARTIST

    The multispectral imaging scanner acquires high-resolution macro images of an artifact in the UV, visible and near-infrared regions. The technique is mainly used for the analysis of paintings and it is employed for the following objectives:

    1) Identification of surface distribution of organic compounds (illumination with UV light)

    2) High resolution documentation (visible light illumination)

    3) Study of the underneath layers for the identification of preparatory drawings and “pentimenti” (use of near-infrared radiation).

  • Infrared microscope Nicolet iN10MX, Thermo Scientific, with accessories for analysis in transmission mode (diamond cell), ATR mode (Conical Germanium (Ge) microATR) and reflection mode (Cassegrain objective)

    The infrared microscopy technique offers the possibility of analyzing organic and inorganic compounds by keeping the area of analysis of the order of magnitude of squared micrometers. The iN10MX microscope, in particular, is used for the characterization of the composition of the different layers, of micrometric thickness, of micro samples collected from an artworks. The technique allows performing single-point or single-point sequential analysis (mapping) on well-defined areas

Consultancy services

The laboratory offers consultancy services in the filed of diagnostic of cultural heritage for the evaluation of the state of conservation and production techniques of both movable and immovable artworks. The non-destructive and micro-destructive techniques available can be used for the analysis of stone, architectural decorations, polychrome surfaces, metal alloys and archaeological material.

Referent

Prof. Rocco Mazzeo