Nonvolatile buffer coating of titanium to prevent its biological aging and for drug delivery.
Nonvolatile buffer coating of titanium to prevent its biological aging and for drug delivery.
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钛的非挥发性缓冲涂层可防止其生物老化并用于药物输送。
DOI：
10.1016/j.biomaterials.2010.02.061
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发表时间：
2010
期刊：
影响因子：
14
通讯作者：
Ogawa,Takahiro
中科院分区：
文献类型：
--
作者：
Suzuki,Takeo;Kubo,Katsutoshi;Hori,Norio;Yamada,Masahiro;Kojima,Norinaga;Sugita,Yoshihiko;Maeda,Hatsuhiko;Ogawa,Takahiro
钛的骨整合能力随着时间的推移而降低。这种现象被定义为钛的生物老化，与亲水性消失和碳氢化合物在钛表面的逐渐积累有关。本研究的目的是研究在钛表面涂覆4-（2-羟基乙基）-1-哌嗪乙磺酸（HEPES）缓冲液（一种非挥发性两性离子化学缓冲剂）是否可以防止钛的生物活性随时间的降解。商业纯钛样品，制备成磁盘和圆柱体，用硫酸酸蚀。三分之一的样品在加工后立即用于实验（新表面），而另外三分之一的样品在黑暗环境条件下储存3个月（3个月表面）。剩余的三分之一在酸蚀后涂有HEPES，并保存3个月（HEPES涂有3个月的表面）。3个月大的表面是疏水性的，而新的和hepes涂层的3个月大的表面是超亲水性的。在初始培养期间，3个月大的表面的蛋白质吸附和附着的成骨细胞数量明显低于新表面和3个月大的hepes涂层表面。与新表面相比，在3个月大的表面上，成骨细胞培养物中的碱性磷酸酶活性和钙沉积降低了50%以上，而在3个月大的表面上，hepes涂层没有发现这种降解。通过推入试验评估，3个月大的种植体的体内骨-种植体整合强度比新种植体低60%。3月龄hepes涂层种植体的推入值与新种植体的推入值相当。在钛表面涂覆含有抗氧化氨基酸衍生物n -乙酰半胱氨酸（NAC）的HEPES，进一步增强了成骨细胞对钛表面的附着，同时由于细胞摄取NAC而增加了细胞内谷胱甘肽储备水平。这些结果表明，HEPES涂层的钛表面保持了至少3个月的超亲水性，并导致生物活性和骨导电性的持续保持，类似于新鲜制备的表面。该涂层技术可用于防止钛的生物老化和递送生物分子以协同增强骨钛融合。
The osseointegration capability of titanium decreases over time. This phenomenon, defined as biological aging of titanium, is associated with the disappearance of hydrophilicity and the progressive accumulation of hydrocarbons on titanium surfaces. The objective of this study was to examine whether coating of titanium surfaces with 4-(2-Hydroxylethyl)-1-piperazineethanesulfonic acid (HEPES) buffer, a nonvolatile zwitterionic chemical buffering agent, could prevent the time-dependent degradation of the bioactivity of titanium. Commercially pure titanium samples, prepared as disks and cylinders, were acid-etched with H2SO4. A third of the samples were used for experiments immediately after processing (new surfaces), while another third were stored under dark ambient conditions for 3 months (3-month-old surfaces). The remaining third were coated with HEPES after acid-etching and were stored for 3 months (HEPES-coated 3-month-old surfaces). The 3-month-old surfaces were hydrophobic, while new and HEPES-coated 3-month-old surfaces were superhydrophilic. Protein adsorption and the number of osteoblasts attached during an initial culture period were substantially lower for 3-month-old surfaces than for new and HEPES-coated 3-month-old surfaces. Alkaline phosphatase activity and calcium deposition in osteoblast cultures were reduced by more than 50% on 3-month-old surfaces compared to new surfaces, whereas such degradation was not found on HEPES-coated 3-month-old surfaces. The strength of in vivo bone-implant integration for 3-month-old implants, evaluated by the push-in test, was 60% lower than that for new implants. The push-in value of HEPES-coated 3-month-old implants was equivalent to that of new implants. Coating titanium surfaces with HEPES containing an antioxidant amino acid derivative, N-acetyl cysteine (NAC), further enhanced osteoblast attachment to the surfaces, along with the increase level of intracellular glutathione reserves as a result of cellular uptake of NAC. These results suggest that HEPES coating of titanium surfaces maintained their superhydrophilicity for at least 3 months and resulted in a continuous retention of bioactivity and osteoconductivity similar to freshly prepared surfaces. This coating technology may be useful for preventing biological aging of titanium and delivering biological molecules for synergistic enhancement of bone-titanium integration.