Titanates and Titanate-Metal Compounds in Biological Contexts.
Titanates and Titanate-Metal Compounds in Biological Contexts.
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DOI：
10.23937/2378-3664/1410009
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
Yen-Wei Chen;Jeanie L. Drury;W. Chung;D. Hobbs;J. Wataha
中科院分区：
文献类型：
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作者：
Yen-Wei Chen;Jeanie L. Drury;W. Chung;D. Hobbs;J. Wataha
金属离子是臭名昭著的环境污染物，有些在极低（ppm级）浓度下会引起毒性。然而，金属离子的氧化还原性质使它们成为生物治疗的有吸引力的候选者。钛酸盐是钛和氧的不溶性颗粒化合物，具有结合金属离子的结晶表面;这些化合物提供了在环境背景下吸收金属离子或在治疗背景下递送金属离子的方法，同时限制全身暴露和毒性。在这两种应用中，钛酸盐的毒理学性质至关重要。迄今为止，钛酸盐的体外毒性的准确测量由于其颗粒性质而变得复杂，这干扰了光密度（OD）依赖性的许多测定，并且目前几乎没有体内钛酸盐毒性数据存在。迄今为止获得的体外天然钛酸盐的相容性数据不一致，并且缺乏机理理解。这些数据表明，天然钛酸盐对几种口腔和皮肤细菌物种几乎没有毒性，但确实以细胞特异性方式抑制哺乳动物细胞代谢。钛化合物结合几种类型的金属离子，包括一些常见的环境毒素，并增强对细菌或细胞的递送。解决钛酸盐的实际适用性仍有大量工作要做。然而，钛酸盐有望作为金属基治疗剂的新型载体或作为环境应用的新型金属清除剂。
Metal ions are notorious environmental contaminants, some causing toxicity at exquisitely low (ppm-level) concentrations. Yet, the redox properties of metal ions make them attractive candidates for bio-therapeutics. Titanates are insoluble particulate compounds of titanium and oxygen with crystalline surfaces that bind metal ions; these compounds offer a means to scavenge metal ions in environmental contexts or deliver them in therapeutic contexts while limiting systemic exposure and toxicity. In either application, the toxicological properties of titanates are crucial. To date, the accurate measurement of the in vitro toxicity of titanates has been complicated by their particulate nature, which interferes with many assays that are optical density (OD)-dependent, and at present, little to no in vivo titanate toxicity data exist. Compatibility data garnered thus far for native titanates in vitro are inconsistent and lacking in mechanistic understanding. These data suggest that native titanates have little toxicity toward several oral and skin bacteria species, but do suppress mammalian cell metabolism in a cells-pecific manner. Titanate compounds bind several types of metal ions, including some common environmental toxins, and enhance delivery to bacteria or cells. Substantial work remains to address the practical applicability of titanates. Nevertheless, titanates have promise to serve as novel vehicles for metal-based therapeutics or as a new class of metal scavengers for environmental applications.