guest ::
| Home > Publications database > Looking Into the Deep: Investigating Micro- and Nanoscale Biomineral Architecture of Marine Organisms Using Advanced Characterization Techniques |
| Home > Publications database > Looking Into the Deep: Investigating Micro- and Nanoscale Biomineral Architecture of Marine Organisms Using Advanced Characterization Techniques |
| Dissertation / PhD Thesis | PUBDB-2024-07058 |
;
2024
Boca Raton, FL, USA
Abstract: Living organisms synthesize and assemble complex bioinorganic composites with enhanced structure and properties to fulfill needs such as structural support and enhanced mechanical function. With the advent of advanced materials characterization techniques, these biomineral systems can be explored with high resolution to glean information on their composition, ultrastructure, assembly, and biomechanics. In this work, the endoskeletal features of two marine organisms are explored. Acantharia are geographically widespread marine planktonic single-celled organisms. Their star-shaped SrSO4 endoskeleton consists of spicules emanating from a central junction, arranged to satisfy crystallochemical and spatial requirements of their orthorhombic crystal lattice. This work used synchrotron X-ray nanotomography and deep-learning guided image segmentation methods to characterize the endoskeleton of 5 types of Acantharia and extrapolate their growth mechanism. The results highlight the diverse morphology of the spicules and spicular junctions that Acantharia achieve while maintaining overall spatial arrangement. Fine structural features, such as interspicular interstices thought to play a role in the robustness of the overall endoskeleton, were resolved. The cartilaginous endoskeleton of sharks is a strong and flexible multicomposite material with excellent mechanical properties that could inspire biomimetic marine applications such as underwater propulsion systems. Variations in mechanical properties along the vertebral column are attributed to compositional contrast and interplay and its three main components: bioapatite mineral, collagen, and glycosaminoglycans. In this work, the micro- and nanoscale chemical and mechanical characteristics of vertebrae of two different sharks – the fast-swimming Blacktip shark and the fastest-swimming Shortfin Mako shark – were investigated using polarized light microscopy, atomic force microscopy, Raman spectroscopy, and nanoindentation. The results link small-scale structural nuances to macroscale inter- and intraspecific differences. Additionally, an in-depth examination of the structure-function relationship using synchrotron X-ray nanotomography and in situ nanoindentation was conducted on the mineralized vertebral cartilage of Blacktip sharks. The results reveal previously uncharacterized structural features in the mineral matrix and elucidate the role ultrastructure plays in dissipating nanomechanical stresses. Overall, this work illustrates how materials characterization techniques can be used to investigate biomineralization phenomena in marine organisms. We can harness the knowledge gained to develop bioinspired materials with enhanced mechanical properties.
|
The record appears in these collections: |
PDF
PDF (PDFA)