The Analysis of a Single Fixed Cell

This instrumentation has exquisite sensitivity, which allows the analysis of single cancer cells (Hu et al., 2004). Our earlier work employed slow separation conditions and a rather primitive photodetection system. Our current system takes roughly 1 h to complete the two-dimensional capillary electrophoresis separation and employs state-of-the-art photodetectors. 

FIGURE 15.10 Landscape image of a two-dimensional capillary electrophoresis analysis of the protein content of a single fixed MCF-7 breast-cancer cell. The data consist of a few high-amplitude components. 

FIGURE 15.11 Expanded view. The data of Fig. 15.10 have been expanded by a factor of 30. 

Two-dimensional capillary electrophoresis of complex protein samples requires careful attention to detail. Tissues and cells should be fixed to prevent degradation. Most conventional fixatives are inappropriate because they produce covalent crosslinks, which are difficult to reverse. We find that ethanol produces decent results when the sample is homogenized with high concentrations of SDS. 

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