To identify preservation fluids in sealed biological specimens using spatially offset Raman spectroscopy (SORS) without opening the containers.
Key Findings:
Successfully identified preservation fluid in 78.5% of cases, with partial agreement in 15%.
Only 6.5% of samples were misclassified or unclassifiable due to reference library limitations or fluorescence interference.
The method distinguished visually similar fluids and provided insights into container materials.
Interpretation:
The SORS method allows for noninvasive identification of preservation fluids and container types, enhancing conservation planning and understanding of historical storage practices.
Limitations:
Classification ambiguities arose from fluorescence effects or secondary components not included in the calibration set.
Some fluid mixtures were not represented in the reference library.
Conclusion:
The study establishes SORS as a practical tool for heritage science, supporting conservation decisions and monitoring chemical changes in preservation fluids over time.
A gold-decorated covalent organic framework grown on titanium dioxide nanotubes enables matrix-free imaging across plants, fingerprints, fruits, and brain tissue
