| abstract |
The present invention provides methods and compositions for labeling, separating and analyzing proteins, particularly specific proteins of interest, in cell lysates or in a mixture of proteins. The protein is labeled with an amine-reactive or thiol-reactive fluorescent dye or an amine-reactive fluorogenic reagent that becomes fluorescent when reacted with an amine group present on the protein. After the labeling step, the proteins in this mixture can be separated and analyzed. In a further embodiment, a tag-binding fluorogenic reagent is added that is capable of binding to a tag present on the tagged protein, and the protein of interest is specifically labeled. |