New Multi-Spectroscopic System Enhances Cultural Heritage Analysis

A recent collaborative study conducted by researchers from several French institutions explored how a new mobile spectroscopic system, billed as SYSPECTRAL, can improve cultural heritage analysis efforts in France. The study’s goal was to see if SYSPECTRAL can provide a comprehensive in situ examination of artifacts with minimal intervention (1). The study, published in Talanta by lead author Vincent Detalle from the Centre de Recherche et de Restauration des Musées de France at CY Cergy-Paris Université, explains how SYSPECTRAL integrates multiple laser-based spectroscopic techniques into a single portable unit, offering a non-invasive approach to material analysis (1).

The cultural heritage industry is currently undergoing several exciting changes. Researchers have explored ways to enhance traditional techniques used in this space by integrating multivariate statistical analysis, novel optical techniques, and mobile instrumentation (2). SYSPECTRAL is the latest example of mobile instrumentation becoming more used in this field.

Ancient cultural site with religious statues and traditional rituals, emphasizing historical and spiritual heritage. Generated by AI. | Image Credit: © tonpreecha - stock.adobe.com

SYSPECTRAL is a compact and mobile system that combines laser-induced breakdown spectroscopy (LIBS), laser-induced fluorescence (LIF), Raman spectroscopy, and reflectance spectroscopy, all operated using a single pulsed laser (1). By integrating these complementary techniques, SYSPECTRAL provides simultaneous elemental, molecular, and colorimetric information from the same analysis point, eliminating inconsistencies that may arise from using separate instruments (1).

SYSPECTRAL can conduct real-time, high-resolution analysis in field conditions. Because the system's software allows for image capture, precise localization, and efficient data acquisition, it allows conservation scientists to make on-site decisions without transporting the data to a laboratory for further analysis. The reflectance spectroscopy component also allows for detailed examination of surface colors and materials, while the LIBS-LIF-Raman package reveals the stratigraphic structure of multi-layered painted samples (1).

As part of the experimental procedure, SYSSPECTRAL was tested on a mock-up oil painting featuring multiple layers to determine whether it can effectively provide insights into the elemental and molecular composition of each layer. Despite relying on low-cost LED sources, the reflectance spectra obtained by SYSPECTRAL aligned well with reference data from hyperspectral imaging systems, confirming the system's reliability (1). Additionally, LIBS and LIF results successfully identified elemental and molecular details corresponding to the stratigraphic structure of the painting (1).

Another key finding in this study was the effectiveness of time-resolved Raman spectroscopy in the mobile setup. The researchers found that the mobile setup of time-resolved Raman spectroscopy performed similarly to laboratory-based Raman analysis (1). Another aspect to the portability of this system was in its lightweight design and its ability to operate independently of a power supply (1). This feature is particularly helpful for researchers conducting measurements and analysis in remote environments. Because SYSPECTRAL can function using a 24V battery, LIBS and reflectance spectroscopy measurement can be used in these remote archaeological sites (1).

A critical component of SYSPECTRAL's functionality is its ability to preserve the integrity of analyzed objects. Optical microscope images taken after laser ablation confirmed that the original materials remained intact, highlighting the system’s non-destructive nature (1). This capability is particularly valuable for the study of fragile or irreplaceable cultural artifacts (1).

In the last part of their article, the researchers discussed future developments in heritage conservation. For example, the research team explained the importance of further exploring time-resolved LIF to build a comprehensive material identification database (1). Such a database could provide a valuable alternative to traditional analysis methods that rely on potentially hazardous chemicals (1).

As this study demonstrates, mobile instrumentation is leading to new advancements in improving non-invasive on-site sampling (3). By integrating multiple spectroscopic techniques into a single, field-deployable system, SYSPECTRAL demonstrated its potential in providing rapid, in-depth, and non-destructive chemical analysis (1). Because of its strengths, SYSPECTRAL can be used as a tool for conservators, researchers, and museum professionals seeking to protect and understand cultural heritage materials (1).

References

1. Bai, X.; Pillay, R.; Brebant, A.; et al. Multi-spectroscopic Characterization System for Cultural Heritage Materials Analysis (SYSPECTRAL): Conception and Example. Talanta 2025, 282, 127027. DOI: 10.1016/j.talanta.2024.127027
2. Workman, Jr., J. Raman Spectroscopy Transforms Cultural Heritage and Forensic Analysis. Spectroscopy. Available at: https://www.spectroscopyonline.com/view/raman-spectroscopy-transforms-cultural-heritage-and-forensic-analysis (accessed 2025-03-31).
3. Workman, Jr., J. Cutting-Edge Raman Spectroscopy Applied for Forensic and Heritage Studies. Spectroscopy. Available at: https://www.spectroscopyonline.com/view/cutting-edge-raman-spectroscopy-applied-for-forensic-and-heritage-studies (accessed 2025-03-31).