Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Department of Biomedical Engineering, Wuhan, HuBei 430074, PR China.
Anal Chim Acta. 2012 Sep 5;741:86-92. doi: 10.1016/j.aca.2012.06.043. Epub 2012 Jul 6.
In this paper, we prepared three types of transferrin-quantum dots conjugates (QDs-Tf) using three different methods (electrostatic interaction, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) coupling, denatured transferrin (dTf) coating). Fluorescence emission spectra, surface characteristics, zeta potentials of quantum dots (QDs) and QDs-Tf fluorescent probes were characterized by spectrophotometer, capillary electrophoresis, and dynamic light scattering. Fluorescent imaging of HeLa cells was also performed by QDs and QDs-Tf fluorescent probes. It was found that the fluorescence imaging performances of QDs-Tf probes prepared by electrostatic interaction and EDC coupling were better compared with the one prepared by dTf coating. Then a real-time single cell detection system was established to quantitatively evaluate cell labeling effects of QDs-Tf fluorescent probes. It was found that for cell labeling efficiency, the proportion of cells labeled by quantum dot probes to a group of cells, QDs-Tf probe prepared by EDC coupling showed the highest labeling efficiency (85.55±3.88%), followed by electrostatic interaction (78.86±9.57%), and dTf coating showed the lowest (40.09±10.2%). This efficiency order was confirmed by flow cytometry results. This study demonstrated the relationship between conjugation methods and the resultant QDs-Tf probes and provided a foundation for choosing appropriate QDs-Tf probes in cell labeling.
在本文中，我们使用三种不同的方法（静电相互作用、1-乙基-3-(3-二甲基氨基丙基)碳二亚胺盐酸盐（EDC）偶联、变性转铁蛋白（dTf）涂层）制备了三种转铁蛋白-量子点缀合物（QDs-Tf）。通过分光光度计、毛细管电泳和动态光散射对量子点（QDs）和 QDs-Tf 荧光探针的荧光发射光谱、表面特性和 Zeta 电位进行了表征。还通过 QDs 和 QDs-Tf 荧光探针对 HeLa 细胞进行了荧光成像。结果发现，与 dTf 涂层制备的 QDs-Tf 探针相比，静电相互作用和 EDC 偶联制备的 QDs-Tf 探针的荧光成像性能更好。然后建立了实时单细胞检测系统，定量评估 QDs-Tf 荧光探针对细胞的标记效果。结果发现，对于细胞标记效率，即一组细胞中被量子点探针标记的细胞比例，EDC 偶联制备的 QDs-Tf 探针显示出最高的标记效率（85.55±3.88%），其次是静电相互作用（78.86±9.57%），dTf 涂层显示出最低的标记效率（40.09±10.2%）。这一效率顺序得到了流式细胞术结果的证实。本研究表明了缀合方法与所得 QDs-Tf 探针之间的关系，并为细胞标记中选择合适的 QDs-Tf 探针提供了基础。
