Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy.
Department of Chemistry and Geological Sciences, University of Modena and Reggio Emilia, Modena, Italy.
J Biomed Mater Res A. 2022 Feb;110(2):504-508. doi: 10.1002/jbm.a.37289. Epub 2021 Aug 4.
Cerium-doped bioactive glasses (Ce-BGs) are implant materials that present high biocompatibility, modulate the levels of reactive oxygen species, and exert antimicrobial activity. The potential of BGs, 45S5, and K50S derived glasses doped with CeO (1.2, 3.6, and 5.3 mol%) to inhibit the growth of pathogen microbes was thoroughly investigated according to the ISO 22196:2011 method properly adapted. A significant reduction of the E. coli charge was detected in all glasses, including the BGs without cerium. The evolution of pH of the medium not inoculated following the immersion of the Ce-BGs was monitored. The presence of cerium did not affect markedly the pH trend, which increased rapidly for both compositions. The change of pH was strongly mitigated by the presence of 200 mM phosphate buffer pH 7.0 (PB) in the medium. In media buffered by PB, the growth of E. coli, Pseudomonas aeruginosa, Listeria monocytogenes, Staphylococcus aureus, and C. albicans was not affected by the presence of BGs doped or not with cerium, suggesting that the antibacterial activity of Ce-BGs is linked to the increase of environmental pH rather than to specific ion effects. However, Ce-BGs resulted promising biomaterials that associate low toxicity to normal cells to a considerable antimicrobial effect, albeit the latter is not directly associated with the presence of cerium.
铈掺杂生物活性玻璃（Ce-BG）是一种具有高生物相容性的植入材料，可调节活性氧的水平并发挥抗菌活性。根据适当调整的 ISO 22196:2011 方法，深入研究了 45S5 和 K50S 衍生的 BG 以及掺杂 CeO（1.2、3.6 和 5.3 mol%）的玻璃抑制病原体微生物生长的潜力。在所有玻璃中，包括不含铈的 BG 中，都检测到大肠杆菌电荷量明显减少。监测了 Ce-BG 浸泡后未接种的培养基 pH 值的演变。铈的存在并未显著影响 pH 趋势，两种成分的 pH 值均迅速升高。在培养基中存在 200 mM 磷酸盐缓冲液 pH 7.0（PB）时，可大大缓解 pH 的变化。在 PB 缓冲的培养基中，E. coli、铜绿假单胞菌、单核细胞增生李斯特菌、金黄色葡萄球菌和白色念珠菌的生长不受掺杂或不掺杂铈的 BG 的影响，表明 Ce-BG 的抗菌活性与环境 pH 值的增加有关，而不是与特定离子的影响有关。然而，Ce-BG 是一种有前途的生物材料，它将低毒性与正常细胞联系起来，并具有相当大的抗菌作用，尽管后者与铈的存在并无直接关系。
