부산대학교 도서관

SUMMARY: Bioactive glasses are used clinically for bone regeneration, and their bioactivity and cell compatibility are often characterised in vitro, using physiologically relevant test solutions. The aim of this study was to show the influence of varying medium characteristics (pH, composition, presence of proteins) on glass dissolution and apatite formation. The dissolution behaviour of a fluoride-containing bioactive glass was investigated over a period of one week in Eagle's Minimal Essential Medium with Earle's Salts (MEM), supplemented with either, (a) acetate buffer, (b) 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer, (c) HEPES + carbonate or (d) HEPES + carbonate + foetal bovine serum. Results show pronounced differences in pH, ion release and apatite formation over 1 week: Despite its acidic pH (pH 5.8 after bioactive glass immersion, compared to pH 7.4 to 8.3 for HEPES-containing media), apatite formation was fastest in acetate buffered (HEPES-free) MEM. Presence of carbonate resulted in formation of calcite (calcium carbonate). Presence of serum proteins, on the other hand, delayed apatite formation significantly. These results confirm that the composition and properties of a tissue culture medium are important factors during in vitro experiments and need to be taken into consideration when interpreting results from dissolution or cell culture studies.