Figure 9.

Scheme for a homogeneous non-competitive immunoassay in CE. In this method the sample is mixed and incubated with labeled antibodies prior to separation by CE. The immunocomplex (i.e., the labeled antibodies that are bound to the analyte) is then separated from the non-bound, labeled antibody on the basis of differences in electrophoretic mobility. The relative size of the immunocomplex peak can then be used to determine how much analyte was present in the original sample. The same approach can be used with a labeled analog of an analyte to determine the amount of antibodies or F_ab fragments for this analyte that are present in a sample.