A Simple and Highly Sensitive Method for Magnetic Nanoparticle Quantitation Using 1H-NMR Spectroscopy
A Simple and Highly Sensitive Method for Magnetic Nanoparticle Quantitation Using 1H-NMR Spectroscopy
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DOI：
10.1016/j.bpj.2009.08.013
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发表时间：
2009-11-04
影响因子：
3.4
通讯作者：
Zhang, Miqin
中科院分区：
文献类型：
--
作者：
Gunn, Jonathan;Paranji, Rajan K.;Zhang, Miqin
氧化铁超顺磁性纳米粒子（SPION）由于其在医学诊断和治疗方面的潜在影响而引起了人们的极大关注。然而，实现这些纳米粒子的可靠和标准化的定量的困难限制了纳米粒子系统的统一研究。目前的测量技术具有有限的灵敏度，并且是复杂的，并且受到个体仪器设置的影响。在这里，使用质子核磁共振（H-1-NMR）光谱的表征方法，可以量化SPION的表面改性。除了在纳米颗粒开发过程中对SPION进行常规定量外，该方法还可用于体外纳米颗粒测定，并可能用于生物分布研究的组织样本。具体而言，溶解的SPION样品的水弛豫率偏移（R-1或R-2）的测量与纳米颗粒浓度相关。未改性和clextran和聚（乙二醇）涂层SPION的SPION浓度和R-1和R-2弛豫率之间的线性相关性超过5个数量级，低于10 ppb的铁。在RAW 264.7巨噬细胞存在下也证实了SPION浓度的定量。在< 10 ng Fe/mL时观察到SPION浓度和弛豫率之间的线性相关性。该方法是一种快速、廉价的SPION定量方法，与目前许多SPION定量分析方法相比具有许多优点。
Iron oxide superparamagnetic nanoparticles (SPIONs) have drawn significant attention because of their potential impact on medical diagnosis and therapy. However, the difficulty of achieving reliable and standardized quantification of these nanoparticles has limited the uniform study of nanoparticle systems. Current measurement techniques have limited sensitivity, and are sophisticated and subject to individual instrumental settings. Here, a characterization method using proton nuclear magnetic resonance (H-1-NMR) spectroscopy is presented that can quantify SPIONs regardless of surface modification. In addition to routine quantification of SPIONs during nanoparticle development, the method can also be used with in vitro nanoparticle assays and potentially with tissue samples for biodistribution studies. Specifically, measurement of water relaxivity shifts (R-1 or R-2) of dissolved SPION samples is correlated with nanoparticle concentration. Unmodified and clextran- and poly(ethylene glycol)-coated SPIONs gave linear correlations between SPION concentration and R-1 and R-2 relaxivities over five orders of magnitude, to below 10 ppb iron. Quantification of SPION concentration was also demonstrated in the presence of RAW 264.7 macrophage cells. A linear correlation between the SPION concentration and relaxivities was observed to < 10 ng Fe/mL. This method is a rapid and inexpensive approach for quantitation of SPIONs and exhibits a number of advantages over many of the current methods for quantitative SPION analysis.