磁纳米传感器与其目标之间的组装状态调节了它们的磁放松反应
Charalambos Kaittanis1, Santimukul Santra, Oscar J Santiesteban
1Nanoscience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, Florida 32826, United States.
Journal of the American Chemical Society
|February 24, 2011
概括
研究人员发现了一种新的磁纳米粒子相互作用,可以增加NMR放松时间 (T2),使得DNA,蛋白质和癌细胞等点的敏感检测成为可能. 这种新的机制为临床应用提供了更快的动力学.
科学领域:
- 纳米技术 纳米技术
- 生物医学工程 生物医学工程
- 分析化学 分析化学
背景情况:
- 磁纳米粒子 (MNP) 通常通过集群来诱导T2减少,以检测目标.
- 传统的MNP测定依赖于目标诱导的聚类,导致减少水质子横向放松时间 (T(2)).
研究的目的:
- 发现和描述一种新的MNP-目标交互机制.
- 为了证明在MNP-连接物相互作用时,T(2) 增加和r(2) 放松性下降.
- 探索这种新机制对敏感生物分子检测的潜力.
主要方法:
- 小分子,蛋白质和核酸的化学结合,以聚烯酸涂层的氧化铁纳米粒子.
- 测量水质子横向NMR放松时间 (T(2) 和放松度 (r(2)).
- 改变目标度和配体形式 (单体与体) 来研究机制过渡.
主要成果:
- 发现了一种新的MNP-目标相互作用,导致T(2) 增加和r(2) 减少.
- 降低r(2) 的比例与连接体数和分子量相反.
- 实现了对Bacillus anthracis DNA (5.3 fmol),霍乱毒素B亚单元 (8 pmol) 和癌细胞的敏感检测.
- 从结合到聚类的机制过渡观察到目标度增加或pentameric Ctb.
结论:
- MNP-目标相互作用的分子架构决定了NMR放松.
- 观察到的T(2) 增加归因于阻碍水扩散的绑定目标.
- 这种新的,更快的MNP交互机制对新的临床和现场检测应用具有前景.
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