Yttrium-Enriched Phosphate Glass-Ceramic Microspheres for Bone Cancer Radiotherapy Treatment

Milborne, Ben; Arjuna, Andi; Islam, Towhidul; Arafat, Abul; Layfield, Robert; Thompson, Alexander; Ahmed, Ifty

Abstract

This study presents the development and characterisation of high yttrium-content phosphate-based glass-ceramic microspheres for potential applications in bone cancer radiotherapy treatment. The microspheres produced via flame spheroidisa-tion, followed by sieving, revealed a lack of aggregation and a narrow size distribution (45-125 µm) achieved across different yttrium oxide to glass ratio samples. EDX analysis showed a significant increase in yttrium content within the microspheres with increasing yttrium oxide to glass ratio samples, ranging from approximately 1 mol % to 39 mol % for 10Y to 50Y microspheres, respectively. Concurrently, a proportional decrease in phosphate, calcium, and magnesium content was observed. Further EDX mapping showed homogenous distribution of all elements throughout the microspheres, indicating uniform composition. XRD profiles confirmed the amorphous nature of the starting P40 glass microspheres, whilst yttrium-containing microspheres exhibited crystalline peaks corresponding to cubic and hexagonal Y 2 O 3 and Y(PO 4) phases, indicating formation of glass-ceramic materials. Ion release studies revealed reduction of all ion release rates from yttrium-containing microspheres compared to P40 microspheres. The pH of the surrounding media was also stable at approximately pH 7 over time, highlighting the chemical durability of the mi-crospheres' produced. In vitro cytocompatibility studies demonstrated both indirect and direct cell culture methods showed favourable cellular responses. The metabolic and alkaline phosphatase (ALP) activity assays indicated comparable or enhanced cell responses on yttrium-containing microspheres compared to the initial P40 glass microspheres. Overall, these findings showed that significantly high yttrium-content phosphate glass-ceramic microspheres could be produced as versatile biomaterials offering potential applications for combined bone cancer radiotherapy treatment and bone regeneration.

Citation

Milborne, B., Arjuna, A., Islam, T., Arafat, A., Layfield, R., Thompson, A., & Ahmed, I. (in press). Yttrium-Enriched Phosphate Glass-Ceramic Microspheres for Bone Cancer Radiotherapy Treatment. Journal of the American Chemical Society,

• Journal Article Type: Article
• Acceptance Date: Oct 14, 2024
• Deposit Date: Oct 16, 2024
• Journal: Journal of the American Chemical Society
• Print ISSN: 0002-7863
• Electronic ISSN: 1520-5126
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Keywords: Yttrium; glass; radiotherapy; bone cancer; bone repair; tissue regeneration
• Public URL: https://nottingham-repository.worktribe.com/output/40582207
• Publisher URL: https://pubs.acs.org/journal/jacsat