The Alexa Fluor® 594 FluoroNanogold streptavidin is covalently conjugated with uniform, 1.4 nm-diameter gold clusters and our bright, red-fluorescent Alexa Fluor® 594 dye (which is spectrally similar to Texas Red dye).. FluoroNanogold™ conjugates can be used as probes in fluorescence microscopy and, when used with our LI Silver Enhancement Kit (Cat. No. L-24919), in immunoblotting, light microscopy or electron microscopy.