The Alexa Fluor® 488 FluoroNanogold streptavidin is covalently conjugated with uniform, 1.4 nm-diameter gold clusters and our exceptionally bright, photostable Alexa Fluor® 488 dye (which is spectrally similar to fluorescein). FluoroNanogold™ conjugates can be used as probes in fluorescence microscopy and, when used with our LI Silver Enhancement Kit (L-24919), in immunoblotting, light microscopy or electron microscopy.