Presentation: Using vibrational spectroscopy to study bone matrix composition and mineralisation

Bone formation is a continuous process occurring across the lifespan: from embryogenesis and skeletal growth through to the lifelong cycle of renewal known as remodelling. The bone matrix itself is a composite material comprising type I collagen fibres reinforced by bioapatite crystals, and the relative quantities, organisation, and maturation of these components are determinants of bone mechanical strength. Understanding how this composition is regulated, and how it changes with age or disease, is therefore central to understanding skeletal fragility.

Our laboratory has employed a suite of vibrational spectroscopic techniques to interrogate bone matrix composition at the tissue level. Using synchrotron-based Fourier-transform infrared microspectroscopy (sFTIRM) and polarised FTIRM (2-angle), we demonstrated in genetically modified mouse models that the signalling protein EphrinB2 governs three distinct aspects of bone mineralisation: the rate of mineral accrual, the degree of carbonate substitution within the bioapatite lattice, and the compaction of collagen fibres within the bone matrix. These findings established a molecular link between cell signalling and the physicochemical properties of bone material.

Since murine bone lacks the osteonal structures that comprise the bulk of adult human cortical bone, we have more recently studied bone composition in cadaveric human specimens from the Melbourne Femur Research Collection, representing healthy bone from a modern urban population. We developed a framework, using sFTIRM and back-scatter electron imaging to identify specific stages of bone maturity. This is revealing differences in how bone matrix is produced and mineralised between young (19–35 years) and older (71–95 years) women, measured by sFTIRM, 4-angle polarised FTIRM, and Raman spectroscopy. These complementary methods provide a multidimensional picture of how ageing influences the bone formation process. The combined data will be presented, with a focus on how spectroscopic approaches are informing our understanding of the processes that control bone material composition and strength.

Speaker biography:

Professor Natalie Sims is Head of the Bone Cell Biology and Disease Unit at St. Vincent's Institute of Medical Research, where she is also the Deputy Director, and is a Professorial Fellow at The University of Melbourne, and at the Australian Catholic University. She completed her PhD at the University of Adelaide in 1995, followed by postdoctoral work at the Garvan Institute (Sydney) and Yale School of Medicine (Connecticut, USA). Her laboratory studies the cellular interactions responsible for development, maintenance and strength of the skeleton, including the IL-6 family of cytokines and estrogen receptor isoforms in bone through the use of genetically altered mouse models and in vitro systems.

Her work has been recognised by the American Society of Bone and Mineral Research Fuller Albright Award (2010) and their Paula Stern Award (2020), and the International Bone and Mineral Society Herbert A Fleisch Award (2013). She was appointed a Fellow of the American Society of Bone and Mineral Research (2018). She is a Deputy Editor of the Journal of Bone and Mineral Research and serves on the Editorial Board of the Journal of Biological Chemistry. She is Past-President of the Australia and New Zealand Bone and Mineral Society and on the Council of the International Federation of Musculoskeletal Research Societies.

Presentation: Live cell imaging using time-lapse FTIR spectroscopy

Synchrotron FTIR live cell imaging is a powerful technique that allows interrogation of biochemical changes in single cells following challenge. It allows analysis of cellular functions in their native environment, is non-destructive and does not require molecular labelling. However, like all techniques, it is not without its limitations. From a physiological viewpoint, mammalian cells do not exist in isolation and are responsive to signals from adjacent or distal cells. From a spectroscopic viewpoint, water absorbs in the infra-red region, and cells contain, and exist in, an aqueous environment.

As a model to investigate lipid dysregulation present in fatty liver, we incubated a mouse hepatocyte cell line with iron, a metal often present in excess in fatty liver. Cells were seeded on to CaF₂ windows and sealed, along with experimental medium, in a modified Bioptechs flow cell available at the Australian Synchrotron’s Mid-IR beamline. In each experiment, a single cell was chosen and mapped hourly for up to 8 hours. Spectra were collected in transmission mode using an 8.3 µm diameter aperture and a 3 µm step size.

Increases in the absorbance of the ester carbonyl band were consistent with an increase in esters (mainly triglycerides) present in iron-loaded cells compared to controls, as well as a rise in the triglyceride concentration over time under both conditions. Using the ratio of methylene to methyl absorbance as a measure of relative lipid chain length, chain length shortened over time in control cells, whereas it lengthened in iron-loaded cells. A pronounced increase in the absorbance of the olefinic band indicated an increase in total lipid unsaturation in iron-loaded cells. Analysis of the second derivative spectrum revealed a shift to higher wavenumbers, consistent with a shift to more poly-unsaturated lipids in the iron-loaded cells.

Synchrotron FTIR imaging is capable of deciphering biochemical processes in live cells over a period of at least 8 hours at sub-cellular resolution. Use of this technique has provided direct evidence of iron-associated lipid accumulation that may lead to hepatic steatosis in whole liver.

Speaker biography:

Dr Ross Graham is a Senior Lecturer in Genetics at Curtin University in WA where he leads a small research group that uses infra-red and X-ray fluorescence techniques to investigate the interaction between metals and lipids in the gastrointestinal system, including liver and pancreas.

Ross completed his PhD at the University of Western Australia then moved to London where he worked on the cobalt-containing vitamin, B12 (cobalamin). Upon return to Perth, he continued his work on biometals at Fremantle Hospital, investigating the link between hepatic iron and cholesterol. Now at Curtin University, he leads a small team using a multi-modal approach of synchrotron IR and XRF paired with molecular biology and traditional biochemistry to understand biometal- and lipid-associated mechanisms of disease.

Presentation: From TerraSpec to Predictive Mineral Intelligence: Quantifying Infrared Spectroscopy for Mining

Near‑infrared (NIR) spectroscopy has been widely used in mineral exploration and mining for more than three decades, most notably through SWIR instruments such as TerraSpec. These tools transformed exploration by enabling rapid, non‑destructive identification of alteration minerals in the field and core shed. Yet despite their widespread adoption, the way NIR data were used changed remarkably little over time. Outputs remained largely qualitative or semi‑quantitative, relied on expert interpretation, and provided indirect proxies for mineral chemistry. Quantitative mineralogy and geochemistry continued to depend on slow, destructive, and expensive laboratory methods such as XRD and ICP‑MS.

This talk examines why NIR spectroscopy in mining plateaued technologically, despite major advances in instrumentation and data acquisition. The key limitation was not hardware, but the absence of validated mineral–spectral–chemistry libraries and predictive models capable of converting infrared spectra into quantitative, decision‑ready information. 

I will then describe how research at the University of Tasmania’s Central Science Laboratory (CSL) and Centre for Ore Deposit and Earth Sciences (CODES) has overcome this bottleneck. By coupling high‑resolution FT‑NIR and FT‑IR spectroscopy with a world‑leading mineral and mineral‑chemistry database, we have developed predictive infrared models that deliver quantitative mineral proportions and mineral chemistry directly from spectral measurements.

These advances are now translated through ScopeIR, a UTAS spin‑out company delivering integrated field and laboratory IR platforms with automated cloud analytics. ScopeIR transforms infrared spectroscopy from a specialist, interpretive technique into a scalable quantitative measurement system, validated against laboratory standards and deployed with major mining companies. The trajectory from TerraSpec to ScopeIR highlights how vibrational spectroscopy, when combined with domain‑specific datasets and predictive modelling, can fundamentally reshape exploration, orebody knowledge, and mining efficiency. 

Speaker biography:

Associate Professor Thomas Rodemann is a vibrational spectroscopist with more than two decades of research experience spanning the development and application of infrared and Raman techniques across science and industry. He is Director of the Central Science Laboratory and Principal Research Fellow in Vibrational Spectroscopy at the University of Tasmania, and since 2024 has served as Technical Lead of ScopeIR, a UTAS spin‑out company advancing quantitative infrared methods for the resources sector.

Trained as a chemist, he has built an interdisciplinary career applying micro‑Raman, FT‑IR, and NIR spectroscopy across geoscience, environmental monitoring, agriculture, and marine science. His work consistently focuses on extracting quantitative, decision‑ready information from complex spectral datasets, bridging the gap between analytical capability and operational use. Over more than twenty years, his research has been supported by major national and industry partners, including the Australian Research Council, AMIRA Global, Wine Australia, and Newcrest Mining, leading to innovations in rapid spectroscopic imaging, mineral systems analysis, and environmental microplastic detection. Through his role with ScopeIR, A/Prof Rodemann contributes to the maturation of predictive infrared spectroscopy from a specialist analytical approach into a scalable, industry‑validated measurement capability.