The quantification of nanomaterials accumulated in various organs is crucial in studying their toxicity and toxicokinetics. However, some types of nanomaterials, including carbon nanomaterials (CNMs), are difficult to quantify in a biological matrix. Therefore, developing improved methodologies for quantification of CNMs in vital organs is instrumental in their continued modification and application. In this study, carbon black, nanodiamond, multi-walled carbon nanotube, carbon nanofiber, and graphene nanoplatelet were assembled and used as a panel of CNMs. All CNMs showed significant absorbance at 750 nm, while their bio-components showed minimal absorbance at this wavelength. Quantification of CNMs using their absorbance at 750 nm was shown to have more than 94% accuracy in all of the studied materials. Incubating proteinase K (PK) for 2 days with a mixture of lung tissue homogenates and CNMs showed an average recovery rate over 90%. The utility of this method was confirmed in a murine pharyngeal aspiration model using CNMs at 30 μg/mouse. We developed an improved lung burden assay for CNMs with an accuracy > 94% and a recovery rate > 90% using PK digestion and UV-Vis spectrophotometry. This method can be applied to any nanomaterial with sufficient absorbance in the near-infrared band and can differentiate nanomaterials from elements in the body, as well as the soluble fraction of the nanomaterial. Furthermore, a combination of PK digestion and other instrumental analysis specific to the nanomaterial can be applied to organ burden analysis.

中文翻译：

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使用紫外-可见分光光度法和蛋白酶 K 消化进行碳纳米材料衍生的肺负荷分析。


不同器官中积累的纳米材料的定量对于研究其毒性和毒代动力学至关重要。然而，某些类型的纳米材料，包括碳纳米材料（CNM），很难在生物基质中定量。因此，开发改进的重要器官 CNM 定量方法有助于其持续修改和应用。在这项研究中，炭黑、纳米金刚石、多壁碳纳米管、碳纳米纤维和石墨烯纳米片被组装并用作 CNM 面板。所有 CNM 在 750 nm 处均显示出显着的吸光度，而其生物成分在此波长处显示出最小的吸光度。在所有研究的材料中，使用 750 nm 处的吸光度对 CNM 进行量化的准确度超过 94%。将蛋白酶 K (PK) 与肺组织匀浆和 CNM 的混合物一起孵育 2 天，平均恢复率超过 90%。该方法的实用性在使用 30 μg/小鼠 CNM 的小鼠咽部抽吸模型中得到了证实。我们开发了一种改进的 CNM 肺负荷测定方法，使用 PK 消化和紫外-可见分光光度法，准确度 > 94%，回收率 > 90%。该方法可应用于任何在近红外波段具有足够吸光度的纳米材料，并且可以将纳米材料与体内元素以及纳米材料的可溶部分区分开来。此外，PK消化和其他针对纳米材料的仪器分析的结合可以应用于器官负荷分析。