Titration allows you to determine the amount of antibody that gives you the best separation of populations in your samples, and the best measure of expression levels. Too little antibody means the cells expressing the marker of interest do not stain as brightly as they could, and may not separate adequately from the negative cells. Too much antibody can increase non-specific binding, which increases the spread and background of the negative population. Both situations result in lower resolution of the measurement.
Titrating Antibodies for Flow Cytometry
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