Combined Morpho-Chemical Profiling of Individual Extracellular Vesicles and Functional Nanoparticles without Labels
Combined Morpho-Chemical Profiling of Individual Extracellular Vesicles and Functional Nanoparticles without Labels
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无标记的单个细胞外囊泡和功能性纳米颗粒的联合形态化学分析
DOI：
10.1021/acs.analchem.0c00607
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发表时间：
2020-04-07
影响因子：
7.4
通讯作者：
Smith, Zachary J.
中科院分区：
文献类型：
--
作者：
Dai, Yichuan;Bai, Suwen;Smith, Zachary J.
生物纳米颗粒是重要的研究目标，但它们的小尺寸和聚集倾向使得它们的异质性难以在真正的单颗粒基础上进行分析。在这里，我们提出了一个无标记的系统，称为“拉曼启用纳米粒子捕获分析”（R-NTA），光学陷阱个别纳米粒子，记录拉曼光谱和跟踪粒子运动，以确定化学成分，大小和折射率。R-NTA具有在单颗粒水平上表征聚集状态和绝对化学浓度的独特能力。我们在NIST标准品和脂质体上验证了该方法，证明R-NTA可以准确地表征尺寸和化学异质性，包括确定组合的形态化学性质，例如单个脂质体中的脂质体数量。应用于细胞外囊泡（EV），我们发现来自癌细胞和非癌细胞的EV之间存在明显差异，并且在喉癌细胞中病理高度表达的TRPP 2离子通道的敲除导致EV更接近于来自正常上皮细胞的EV。有趣的是，EV含量的差异存在于EV的小亚群中，突出了单颗粒测量的重要性。这些实验证明了R-NTA系统测量和表征生物纳米颗粒的形态化学异质性的能力。
Biological nanoparticles are important targets of study, yet their small size and tendency to aggregate makes their heterogeneity difficult to profile on a truly single-particle basis. Here we present a label-free system called 'Raman-enabled nanoparticle trapping analysis' (R-NTA) that optically traps individual nanoparticles, records Raman spectra and tracks particle motion to identify chemical composition, size, and refractive index. R-NTA has the unique capacity to characterize aggregation status and absolute chemical concentration at the single-particle level. We validate the method on NIST standards and liposomes, demonstrating that R-NTA can accurately characterize size and chemical heterogeneity, including determining combined morpho-chemical properties such as the number of lamellae in individual liposomes. Applied to extracellular vesicles (EVs), we find distinct differences between EVs from cancerous and noncancerous cells, and that knockdown of the TRPP2 ion channel, which is pathologically highly expressed in laryngeal cancer cells, leads the EVs to more closely resemble EVs from normal epithelial cells. Intriguingly, the differences in EV content are found in small subpopulations of EVs, highlighting the importance of single-particle measurements. These experiments demonstrate the power of the R-NTA system to measure and characterize the morpho-chemical heterogeneity of bionanoparticles.