New violet-excitable reagents for multicolor flow applications.

We have recently added three new fluorophores-BD Horizon™ V450, BD Horizon V500, and BD Horizon V550 (V450, V500, and V550; BD Biosciences, San Jose, CA) to our existing AmCyan product, forming a group of four violet-excitable dyes from which we have produced functional antibody conjugates. These conjugates, with emission maxima that range from 450 to 535 nm, are compatible with multilaser flow cytometry (FCM) and can be used for polychromatic FCM in three-color or two-color combinations; in fact, V500 fills a spectral opening that has thus far not been exploited by other manufacturers of FCM reagents. We here report that conjugates based on BD Horizon dyes performed well within a useful sensitivity range, established by testing a representative group of violet-excitable FCM reagents currently available, and that V500 has better compatibility with FITC in multicolor applications than does AmCyan.