Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB, Canada.
Nanotechnology. 2011 Jul 15;22(28):285103. doi: 10.1088/0957-4484/22/28/285103. Epub 2011 Jun 8.
1-Ethyl-3-(3-dimethylaminopropyl) carbondiimide hydrochloride (EDC) is commonly used as a crosslinker to help bind biomolecules, such as DNA plasmids, with nanostructures. However, EDC often remains, after a crosslink reaction, in the micro-aperture of the nanostructure, e.g., carbon nanotube. The remaining EDC shows positive green fluorescent signals and makes a nanostructure with a strong cytotoxicity which induces cell death. The toxicity of EDC was confirmed on a breast cancer cell line (MCF-7) and two leukemic cell lines (THP-1 and KG-1). The MCF-7 cells mainly underwent necrosis after treatment with EDC, which was verified by fluorescein isothiocyanate (FITC) annexin V staining, video microscopy and scanning electronic microscopy (SEM). If the EDC was not removed completely, the nanostructures with remaining EDC produced a green fluorescent background that could interfere with flow cytometry (FACS) measurement and result in false information about GFP plasmid delivery. Effective methods to remove residual EDC on macromolecules were also developed.
1-乙基-3-(3-二甲基氨基丙基)碳二亚胺盐酸盐（EDC）通常被用作交联剂，以帮助将生物分子，如 DNA 质粒，与纳米结构结合。然而，交联反应后，EDC 经常残留在纳米结构的微孔中，例如碳纳米管。残留的 EDC 显示出阳性绿色荧光信号，并使具有强烈细胞毒性的纳米结构诱导细胞死亡。EDC 的毒性已在乳腺癌细胞系（MCF-7）和两种白血病细胞系（THP-1 和 KG-1）上得到证实。EDC 处理后 MCF-7 细胞主要发生坏死，这通过荧光素异硫氰酸酯（FITC） Annexin V 染色、视频显微镜和扫描电子显微镜（SEM）得到验证。如果未完全去除 EDC，则残留 EDC 的纳米结构会产生绿色荧光背景，这可能会干扰流式细胞术（FACS）测量，并导致 GFP 质粒转导的错误信息。还开发了去除大分子上残留 EDC 的有效方法。
