Abstract Quantification of the cellular uptake of nanomaterials is crucial for studies of their toxicity and medical applications. However, our knowledge of the behaviors of carbon nanotubes (CNTs) in cells or tissues remains incomplete due to the lack of appropriate methods for quantitative analysis. Here, we present a unique methodology for quantitatively assessing the cellular uptake of CNTs, taking advantage of their absorption of light in the near-infrared region. Measurement of CNT concentration in cell lysates by monitoring absorbance at 750 nm enabled highly accurate quantification of CNTs accumulated within cells. In a comparative study of eight commercially available CNTs with dynamic size ranging from 30 to 400 nm, we obtained the first quantitative evidence that cellular uptake of CNTs by RAW264.7 macrophages depends on their sizes, specifically on the widths of their bundles in dispersion, regardless of type or manufacturer. Specifically, uptake of CNTs increased linearly with dynamic size, and cytotoxicity increased along with uptake.

中文翻译：

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巨噬细胞对碳纳米管的尺寸依赖性细胞摄取：比较和定量研究

摘要 纳米材料细胞摄取的量化对于研究它们的毒性和医学应用至关重要。然而，由于缺乏适当的定量分析方法，我们对细胞或组织中碳纳米管 (CNT) 行为的了解仍然不完整。在这里，我们提出了一种独特的方法来定量评估 CNT 的细胞吸收，利用它们在近红外区域的光吸收。通过监测 750 nm 处的吸光度来测量细胞裂解物中的 CNT 浓度，可以高度准确地量化细胞内积累的 CNT。在对动态尺寸范围为 30 到 400 nm 的八种市售碳纳米管进行比较研究时，我们获得了第一个定量证据，表明 RAW264.7 巨噬细胞对碳纳米管的细胞摄取取决于它们的尺寸，特别是在其分散束的宽度上，无论类型或制造商如何。具体而言，碳纳米管的吸收随动态尺寸线性增加，细胞毒性随吸收增加。