Abstract：
Functionalized single-walled carbon nanotubes (SWCNTs) hold immense potential for diverse biomedical applications due to their biocompatibility and optical properties, including near-infrared fluorescence. Specifically, SWCNTs have been utilized to target cells as a vehicle for drug delivery and gene therapy, and as sensors for various intracellular biomarkers. While the main internalization route of SWCNTs into cells is endocytosis, methods for enhancing the cellular uptake of SWCNTs are of great importance. In this research, we demonstrate the use of a transfecting reagent for promoting cell internalization of functionalized SWCNTs. We explore different types of SWCNT functionalization, namely single-stranded DNA (ssDNA) or polyethylene glycol (PEG)-lipids, and two different cell types, embryonic kidney cells and adenocarcinoma cells. We show that internalizing PEGylated functionalized SWCNTs is enhanced in the presence of the transfecting reagent, where the effect is more pronounced for negatively charged PEG-lipid. However, ssDNA-SWCNTs tend to form aggregates in the presence of the transfecting reagent, rendering it unsuitable for promoting internalization. For all cases, cellular uptake is visualized by near-infrared fluorescence microscopy, showing that the SWCNTs are typically localized within the lysosome. Generally, cellular internalization was higher in the adenocarcinoma cells, thereby paving new avenues for drug delivery and sensing in malignant cells.
摘要：
功能化的单壁碳纳米管（SWCNT）由于其生物相容性和光学特性，在各种生物医学应用中具有巨大的潜力。包括近红外荧光。具体来说,SWCNT已被用于靶向细胞作为药物递送和基因治疗的载体，并作为各种细胞内生物标志物的传感器。虽然SWCNT进入细胞的主要内化途径是胞吞作用，增强SWCNT细胞摄取的方法非常重要。在这项研究中,我们证明了转染试剂用于促进功能化SWCNT的细胞内化的用途。我们探索了不同类型的SWCNT官能化，即单链DNA（ssDNA）或聚乙二醇（PEG）-脂质，和两种不同的细胞类型，胚胎肾细胞和腺癌细胞。我们表明，内化聚乙二醇化官能化的SWCNT在转染试剂的存在下增强，其中效果对于带负电荷的PEG-脂质更明显。然而,ssDNA-SWCNT倾向于在转染试剂的存在下形成聚集体，使其不适合促进内化。对于所有情况,通过近红外荧光显微镜观察细胞摄取，表明SWCNT通常位于溶酶体内。一般来说,细胞内化在腺癌细胞中更高，从而为恶性细胞中的药物递送和传感开辟了新的途径。
