Oral Presentation Royal Australian Chemical Institute National Congress 2026

The nanoscale chemistry of bioceramic bone implant materials “in action”, revealed by atom probe (136989)

Natalie P Holmes 1
  1. The University of Sydney, Sydney, NOT US OR CANADA, Australia

This seminar focuses on the nanoscale chemistry of bioceramic bone implants in vivo, and probing dissolution and ion transport into bone tissue in three dimensions with atom probe tomography. Atom probe tomography is a unique three-dimensional analytical technique capable of mapping the spatial positions of individual atoms within a material, hence providing localised compositional information for defined volumes. This powerful technique has the capacity to detect every element in the periodic table, with parts-per-million sensitivity. We recently published the first report of the near-atomic scale chemical composition of in vivo bone formed in a bioceramic scaffold (strontium-hardystonite-gahnite) (Li, 2019) after 12-month implantation in a large bone defect in sheep tibia, by atom probe (Holmes, 2023). This study detected elements from the degrading bioceramic implant, particularly aluminium (Al), in both the newly formed bone and in the original mature cortical bone tissue at the perimeter of the bioceramic implant. Atom probe tomography confirmed that trace elements were released from the bioceramic and were actively transported into the newly formed bone. Our work combines atom probe tomography (near-atomic resolution) and nanoSIMS (sub-micron resolution) to enable chemical composition changes at precise locations within the tissue/bioceramic interface to be studied. The influence of bioceramic scaffold implants on the composition of newly formed bone in vivo, as well as adjacent mature bone, is still not fully understood. Our work shows that advances in laser-assisted atom probe tomography now allow detailed investigation of such biological materials (Holmes, 2025). This nanostructural analysis tool has the potential to offer new insights into the mode of action of bioceramic scaffolds, and to assess the osteoproductive properties of next-generation implant materials.

  1. J. J. Li, C. R. Dunstan, A. Entezari, Q. Li, R. Steck, S. Saifzadeh, A. Sadeghpour, J. R. Field. A. Akey, M. Vielreicher, O. Friedrich, S.-I. Roohani-Esfahani, H. Zreiqat, Advanced Healthcare Materials, 2019, 8, 1801298.
  2. N. P. Holmes, I. Roohani, A. Entezari, P. Guagliardo, M. Mirkhalaf, Z. Lu, Y.-S. Chen, L. Yang, C. R. Dunstan, H. Zreiqat, J. M. Cairney, Acta Biomaterialia, 2023, 162, 199-210.
  3. N. P. Holmes, Y.-S. Chen, R. Niu, H. McGuire, E. Chen, J. M. Cairney, Current Opinion in Solid State and Materials Science, 2025, 39, 101241.