Hi, I´ve been having issues with polystyrene Functional Beads for Cytometric Bead Array from BD Bioscience. In my experiment, I covalently link water-soluble proteins to the surface of these functional beads and I have some troubles with storage. When I do cytometric analysis it seems like the beads fell apart. Does anyone here have any idea what to use to preserve them? Thanks in advance .

 

This is odd. We use beads in sizes between about 50 nm to 20 microns and they were found to be quite stable (as per light microscopy, SEM and DLS) in a variety of aqueous buffers. The have the tendency to aggregate, though. Or do you mean that they lose their functional groups?