Event Abstract Back to Event The influence of increasing Sr2+content on the structure of borate-based glasses. Yiming Li1, 2, Dj Curran1, 2, E Schemitsch2, P Zalzal3, M Papini1, Aw Wren4 and Mr Towler1, 2, 5 1 Ryerson University, Mechanical and Industry Enginerring, Canada 2 St. Michael’s Hospital, 2Keenan Research Centre, Canada 3 3Oakville Memorial Hospital, Canada 4 Alfred University, 4Inamori School of Engineering, United States 5 University Malaya, Department of Biomedical Engineering, Malaysia Introduction: Strontium, when incorporated as a network modifier, has been reported to increase the hardness and reduce the dissolution of a glass[1]. Additionally, Sr2+ can stimulate bone formation in vitro[2]. This project was designed to investigate the influence of increasing Sr2+ content on the structure of a borate-based glass series expected to be applied as bioactive coatings on the Ti-6Al-4V implants. Methods: Glass series were formulated (Table I) by melt quenching. X-ray Diffraction (XRD), Differential Thermal Analysis (DTA) and Raman Spectroscopy were employed to investigate any changes in the glass structure as a result of increasing Sr content. Results and Discussions: The absence of peaks in the XRD traces confirm the amorphous nature of each glass. The glass transition temperatures (Tg) of the glass series decreased with addition of up to 5 mol% of Sr2+, and then increased with increased additions of Sr2+. It is apparent that the Raman spectra (Figure 1) are dominated by a broad peak centered at 1320 cm-1 and a shoulder at 1500 cm-1. In addition, three Raman bands were detected at 770 cm-1, 860 cm-1 and 940 cm-1. The intensity of the band at 770 cm-1 decreased with increasing Sr2+. However, the intensity of bands at 860 cm-1 and 940 cm-1 increased with Sr2+ content. The symmetric breathing vibration of [BØ4] is assigned at around 770 cm-1[3]. The increasing intensity of Raman bands at 860 cm-1 and 940 cm-1 and the larger peak areas under 860 cm-1, 1320 cm-1 and 1500 cm-1 indicate increased presence of [BØ2O]- and [B2ØO4]4- group introduced by non-bridging oxygen (NBO) within the glasses as more Sr2+ is incorporated. [3] Tg of borate glasses increased with the increase Metal-oxygen boding (FR-O). Therefore, more ionic Sr-O bonding increases Tg of the glass series. Table 1. Compositions of the glass series (mol%). Figure 1. Raman spectroscopy of the borate glass series. Conclusions: Increasing Sr2+ content induced higher amounts of NBO expected to decrease Tg. However, Tg increased with the addition of more than 5 mol% of Sr2+. This can be explained by the fact that enough Sr2+was present to induce more Sr-O bonding providing additional cross-links across borate segments of the glass network. The Canadian Institute of Health Research (CIHR); The Natural Sciences and Engineering Research Council of Canada (NSERC) through the Collaborative Health Research Project (CHRP) program (grant #315694-DAN)