| Capillary electrophoresis (CE) is an ideal tool for chemical cytometry. Due to its small injection volume, commonly in the picoliter range, CE is capable of analyzing a very small sample size. The volume of mammalian cells, which commonly have diameters of 10-20 microm, is usually around 500 fL. CE with laser-induced fluorescence detection (CE-LIF) with a sheath-flow cuvette is ideal for detecting small quantities of analyte since it can routinely detect in the yoctomole (10-24) range. These systems provide the very high efficiency typical of classic CE with the convenient interface of high-sensitivity detection. Most importantly, multiple-capillary systems, which were originally developed for high-throughput DNA sequencing, provide an avenue to high-throughput single cell analysis.;A five-channel CE-LIF instrument was developed to analyze five single cells simultaneously. The multi-channel instrument was modified to accommodate a new arrangement of five capillaries in order to integrate them with an array of patterned single cells. Arrays fabricated from glass, indium-tin oxide (ITO) coated glass, and poly(dimethylsiloxane) (PDMS) were investigated. The array must efficiently trap the cells, yet allow for the cell (or cellular content) to be brought into the capillary with excellent capillary-to-cell alignment. The array that provided the most favorable characteristics was constructed of a base of ITO coated glass with a PDMS mold as a cell trapping surface. |
