单细胞分析中的荧光标记化学

Fluorescent Labeling Chemistry in Single Cell Analysis

细胞内组分复杂、含量低,因此测定单细胞内化学组分的分析方法必须具有灵敏度高、选择性好和分辨率高的特点。高灵敏度的荧光检测技术是单细胞分析中应用最多的检测方法之一。但是细胞内绝大部分物质其天然态是没有荧光的,且由于细胞膜的阻碍,衍生试剂不能自由地进入细胞内。为了使衍生试剂透过细胞膜标记细胞内待测物质而不引起显著的稀释效应,已进行了大量的研究工作。本文综述了在单细胞分析中常用的荧光标记方法,包括细胞作为微反应器的衍生法,借助于脂质体与聚乙二醇(PEG)等增加细胞膜通透性的衍生方法和在毛细管/芯片毛细管电泳分析单细胞时柱上衍生和柱后衍生法以及量子点的标记法等。对这些方法的原理、特点和在单细胞分析中的应用也做了较为详细的阐述。

The technical requirements for the determination of the chemical composition of individual cells are strict due to the complex composition and minute amount of analyte present in a single cell. Due to its high sensitivity, fluorescence detection is one of the dominant detection techniques used for single cell analysis. However, a large number of compounds found in single cells are nonfluorescent and cell membrane acts as a barrier to the free diffusion of derivatization reagents into cells. In order to introduce derivatization reagents into cells to label intracellular analytes without evident dilution, considerable efforts on derivatization of intracellular contents have been made. The intracellular labeling methods developed for single cell analysis are summarized in this review, including cell itself acting as a microreaction chamber for derivatization, derivatization mediated by liposome or polyethylene glycol to increase permeabilization of cell membrane, on- and post-column derivatization during single cell analysis with capillary electrophoresis or microchip electrophoresis and labelling of ceils with quantum dots. Their principles, characters and applications in single cell analysis are also described in detail.