Alexa Fluor 610—R-phycoerythrin goat anti—mouse IgG is labeled with our tandem dye construct that excites at 488 nm and emits at 630 nm, and is prepared from affinity-purified antibodies that react with IgG heavy chains and all classes of immunoglobulin light chains from mouse. To minimize crossreactivity, it has been adsorbed against human IgG and human serum prior to conjugation.