多牙保护的合金纳米晶体:合作降水和表面层流失的pH控制
1Department of Biomedical Engineering, Emory University, 101 Woodruff Circle, Suite 2001, Atlanta, Georgia 30322, USA.
Journal of the American Chemical Society
|April 23, 2011
概括
多牙聚合物联体使得pH敏感的金纳米晶 (AuNC) 的合成成为可能. 这些智能纳米粒子可以通过微小的pH值变化在有机溶剂中快速分离或溶解,有助于向药物输送.
科学领域:
- 纳米技术纳米技术
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
背景情况:
- 合金纳米晶体 (AuNCs) 对生物医学应用非常有价值.
- 控制AuNC的溶解度和特性对于它们的有效使用至关重要.
- 现有的稳定方法往往缺乏可调节的响应特性.
研究的目的:
- 使用多牙聚合物联体合成新型AuNC.
- 为了研究这些AuNCs的pH响应溶解度和脱落行为.
- 探索这些AuNC作为成像和治疗的智能纳米粒子的潜力.
主要方法:
- 合成AuNCs使用带有碳酸和酸组的多酸聚合物联体.
- 描述AuNC的大小,稳定性和可溶性.
- 研究pH诱导的可溶性过渡 (pH4.85至4.25).
- 对聚合物层脱落和溶剂兼容性的分析.
主要成果:
- 合成的AuNC具有大尺寸可调性和pH敏感性质.
- 在0.6pH单位下降时,可溶性从可溶性过渡到不溶性.
- 聚合物外层不可逆转的脱落,使其在非极性有机溶剂中具有可溶性.
- 聚合物涂层对小型有机分子的透性.
结论:
- 多牙聚合物联体提供了一个多功能平台,用于创建可调节的,对pH响应的AuNC.
- 轻易的pH触发的可溶性变化允许有效的隔离和再分散.
- 这些AuNC显示了作为"智能"纳米颗粒的承诺,用于有针对性的传递和成像,由生理学pH值变化激活.
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