多聚乙烯甘醇) 连接物在极端条件下为半导体和金属纳米晶体提供合体稳定性
Michael H Stewart1, Kimihiro Susumu, Bing C Mei
1Optical Sciences Division, Naval Research Laboratory, Washington, D.C. 20375, USA.
Journal of the American Chemical Society
|June 29, 2010
概括
新的聚乙烯甘醇 (PEG) 基联体为量子点 (QD) 和金纳米粒子 (AuNPs) 提供了特殊的体稳定性. 这些配体确保纳米粒子在极端pH值,高盐度和富含醇的条件下稳定,用于先进的生物应用.
科学领域:
- 纳米技术纳米技术
- 材料科学 材料科学 材料科学
- 生物结合化学 生物结合化学
背景情况:
- 半导体量子点 (QD) 和金纳米粒子 (AuNP) 是有价值的纳米材料,在生物成像和诊断中具有应用.
- 在恶劣条件下 (极端pH值,高盐度,富含醇的环境) 实现长期的体稳定性仍然是这些纳米粒子面临的重大挑战.
- 开发强大的表面配体对于提高纳米粒子稳定性和扩大它们在生物系统中的实用性至关重要.
研究的目的:
- 设计和合成基于多乙烯糖醇 (PEG) 的新型配体,具有多牙基.
- 评估这些配体在赋予量子点 (QD) 和金纳米粒子 (AuNP) 特殊的体稳定性方面的有效性.
- 在生物相关研究中展示这些稳定纳米粒子的潜力,这些研究需要抵抗降解.
主要方法:
- 使用迈克尔添加和碳二胺联,合成 bis ((thioctic acid) -PEG-OCH ((3) 和 bis ((dihydrolipoic acid) -PEG-OCH ((3) 连接物.
- 通过合成的配体稳定了CdSe-ZnS核心外QDs和AuNPs的分散的制备和表征.
- 在广泛的pH范围 (1.113.9) 和高NaCl度 (2M) 的情况下测试纳米粒子分散的合稳定性.
- 评估AuNPs对DTT竞争的抵抗力,最高可达1.5M.
- 组装和测试QD核定位信号生物结合物.
主要成果:
- 在极端pH和高盐条件下,合成的基于PEG的配体为QD和AuNP提供了显著的长期体稳定性.
- 通过这些配体功能化的AuNP表现出强烈的抵抗力,可以通过高度的迪西二醇来取代.
- 稳定的QD-生物结合物被成功组装在一起,显示出增强的细胞内吸收.
- 连接体的四牙性质是纳米晶体 koloid 稳定性改善的关键.
结论:
- 基于PEG的新型配体具有多牙基组,在具有挑战性的环境中有效稳定QD和AuNP.
- 这些稳定纳米粒子适用于各种与生物相关的应用,要求耐极端pH值,高离子强度和富含醇的条件.
- 开发的配体为生物研究中更强大,更可靠的基于纳米粒子的探针和生物结合物铺平了道路.
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