Hans Hallen and researchers at North Carolina State University have applied Resonance Raman (RR) imaging to fossilized soft tissues from Brachylophosaurus canadensis and T. rex, detecting hemoglobin remnants that are demonstrably native to the dinosaurs; not contamination; and tracing the molecular changes it underwent over time. This research, published , sheds new light on how biomolecules survive deep time.
Long, B. J. N., Zheng, W., Schweitzer, M., & Hallen, H. D. (2025). Resonance Raman confirms partial haemoglobin preservation in dinosaur remains. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 481(2321). https://doi.org/10.1098/rspa.2025.0175
RR imaging pinpoints molecules by using light tuned to their specific absorption bands; making targeted signals from heme globin structures stand out amid the fossil’s complex background. This allows researchers to “find the needle in the haystack,” identifying both preserved hemoglobin and its breakdown products.
By comparing dinosaur samples with modern ostrich bone and human blood, the study confirmed hemoglobin is present. Moreover, the data showed the degradation path: as hemoglobin breaks down, iron-rich fragments can bind to goethite, a mineral, helping stabilize these remnants over millions of years.
Hans Hallen, professor of physics at NC State stated.
“Raman spectroscopy essentially uses light waves to identify a molecule’s energetic ‘fingerprint. “Resonance Raman, which we use here, takes that process one step further by using light that is already tuned to the molecule of interest; so only that type of molecule will resonate.”
A key advance here is that RR imaging verifies both molecular bonds and structural context. That distinction enabled the team, including Mary Schweitzer, to rule out contamination: only endogenous hemoglobin-linked structures produce the precise spectral signature observed.
Previous studies have noted soft tissue preservation in fossils—including blood vessel; like structures, collagen, and cells. Mechanisms such as Fenton chemistry have been proposed to explain how biomolecules might survive fossilization.
This new work adds resolution: it not only confirms hemoglobin persists but also maps its chemical transformation. Findings like goethite association offer insight into diagenetic processes that protect protein fragments.
- Analytical Frameworks: RR imaging could be expanded to study other long-lived biomolecules in ancient remains.
- Biomolecular Stabilization: Understanding mineral-related preservation might inform biomaterial engineering or synthetic preservation strategies.
- Paleobiological Insights: Molecular preservation enriches reconstructive models of ancient physiology and fossilization dynamics.
Adrian graduated with a Masters Degree (1st Class Honours) in Chemical Engineering from Chester University along with Harris. His master’s research aimed to develop a standardadised clean water oxygenation transfer procedure to test bubble diffusers that are currently used in the wastewater industry commercial market. He has also undergone placments in both US and China primarely focused within the R&D department and is an associate member of the Institute of Chemical Engineers (IChemE).
