Comparative study of mobile Raman instrumentation for art analysis

Area of Science:

• Archaeometry
• Materials Science
• Analytical Chemistry

Background:

• Non-destructive analysis is crucial for art conservation and cultural heritage studies.
• Raman spectroscopy offers a non-invasive method for material identification.
• Advancements in mobile Raman instrumentation enable in-situ analysis of artworks.

Purpose of the Study:

• To evaluate the performance of five distinct mobile Raman instruments.
• To assess their capabilities in analyzing organic and inorganic pigments through varnish layers.
• To determine their suitability for identifying biomaterials and analyzing complex sample areas.

Main Methods:

• Comparative performance evaluation of five mobile Raman spectrometers (Renishaw RA100, RX210, Ocean Optics RSL-1, Delta Nu Inspector Raman, MArtA).
• Analysis conducted across three independent laboratories to ensure reproducibility.
• Testing included spectral resolution, calibration accuracy, laser filtering, and penetration through varnish.
• Spectra acquired from simulated artwork samples, including pigments and biomaterials, and from difficult-to-access regions.

Main Results:

• Instruments demonstrated varied spectral resolution and calibration stability.
• Performance in analyzing pigments through varnish layers differed significantly among devices.
• Identification of biomaterials was feasible, though sensitivity varied.
• The ability to analyze samples in constrained or hard-to-reach areas was assessed for each instrument.

Conclusions:

• Mobile Raman spectroscopy is a viable technique for non-destructive analysis in archaeometry.
• Instrument selection depends on specific analytical needs, such as pigment identification or biomaterial analysis.
• Further development is needed to optimize performance for routine analysis of complex cultural heritage objects.