Scientists have efficiently analyzed Charles Darwin’s unique specimens from his HMS Beagle voyage (1831 to 1836) to the Galapagos Islands.
Remarkably, the specimens have been analyzed with out opening their 200-year-old preservation jars.
Analyzing 46 historic specimens
The research examined 46 historic specimens on the Pure Historical past Museum, London, together with mammals, reptiles, fish, jellyfish, and shrimps collected by Darwin and different naturalists. The work is revealed within the journal ACS Omega.
It was discovered that conventional preservation strategies differed by species and period.
Mammals and reptiles have been sometimes mounted in formalin and saved in ethanol, whereas invertebrates is perhaps stored in formalin, buffered options, or mixtures containing components like glycerol.
80% of samples appropriately recognized
The method appropriately recognized fluids in roughly 80% of instances examined, with partial identification in one other 15%.
It additionally decided the sorts of glass or plastic containers used, offering insights into how storage strategies have advanced over time.
The analysis was carried out by a collaboration between the Science and Know-how Services Council (STFC), the Pure Historical past Museum and Agilent Applied sciences.
Transportable laser strategies
Researchers used a conveyable laser spectroscopy technique known as Spatially Offset Raman Spectroscopy (SORS) to look via glass and determine the chemical composition of preservation fluids.
SORS performs chemical evaluation by shining a laser gentle right into a container and inspecting the adjustments in wavelength that happen when the sunshine is mirrored.
These adjustments point out the presence of various chemical parts inside it.
SORS, initially developed at STFC’s Central Laser Facility, is similar method which is utilized in airport scanners everywhere in the world via Agilent Applied sciences.
Dr. Sara Mosca, STFC Central Laser Facility stated, “Till now, understanding what preservation fluid is in every jar meant opening them, which dangers evaporation, contamination, and exposing specimens to environmental harm. This system permits us to observe and look after these invaluable specimens with out compromising their integrity.”
Impression for museums worldwide
There are over 100 million fluid-preserved specimens housed in museums worldwide.
For assortment curators, realizing the precise composition of preservation fluids is important for monitoring specimen situation.
The power to investigate preservation fluids non-invasively affords conservators and curators a brand new device for monitoring assortment well being and intervening earlier than issues come up.
Reworking the research of pure historical past
Wren Montgomery, analysis technician on the Pure Historical past Museum, says, “As a part of NHM Unlocked, right here on the Museum we are able to analyze jars containing specimens with out opening and disturbing their integrity. This work is the subsequent step in demonstrating the Museum’s dedication to remodeling the research of pure historical past.
“Analyzing the storage situations of treasured specimens, and understanding the fluid by which they’re stored, may have large implications for the way we look after collections and protect them for future analysis for years to return.”
Publication particulars
Ana Blanco et al, In Situ Evaluation of Historic Preservation Fluids in Sealed Containers with Spatially Offset Raman Spectroscopy, ACS Omega (2026). DOI: 10.1021/acsomega.5c09045
Offered by UK Analysis and Innovation
