Surface controlled calcium phosphate formation on three-dimensional bacterial cellulose-based nanofibers

Area of Science:

• Biomineralization
• Materials Science
• Nanotechnology

Background:

• Understanding early calcium phosphate (Ca-P) formation on nanosized substrates is crucial for elucidating molecular-level biomineralization mechanisms.
• Bacterial cellulose (BC)-based nanofibers offer a unique platform for studying biomineralization due to their nanoscale structure and biocompatibility.

Purpose of the Study:

• To investigate the in situ formation of Ca-P minerals on BC-based nanofibers.
• To determine the influence of surface coating on the Ca-P mineral formation pathway.
• To gain insights into the molecular mechanisms of biomineralization using advanced spectroscopy.

Main Methods:

• In situ X-ray absorption near-edge structure (XANES) spectroscopy was employed to monitor Ca-P formation.
• X-ray diffraction (XRD) analysis was used in conjunction with XANES to characterize mineral phases.
• Surface-modified BC nanofibers were utilized as templates for Ca-P precipitation.

Main Results:

• XANES and XRD analyses confirmed the initial formation of amorphous calcium phosphate (ACP).
• The transformation pathway proceeded from ACP to β-tricalcium phosphate (TCP), then octacalcium phosphate (OCP), and finally hydroxyapatite (HAP) on phosphorylated BC nanofibers.
• The nature of the coating material on the nanofibers significantly affected the nascent precursor formation and its subsequent transformation process.

Conclusions:

• The study provides novel insights into the sequential transformation of calcium phosphate phases during biomineralization on nanofibrous templates.
• The findings highlight the critical role of surface chemistry in directing mineralization pathways.
• This research paves the way for developing novel bioinspired nanostructured materials with tailored properties for various applications.