These light-emitting types of dyes like rhodamine & aniline blue are used to label proteins
Efficient conversion of these fluorescein isologues to rhodamine-like dyes .... 
useful labels for PALM, including photoactivatable fluorescent proteins and... [DOC] [TLE] US20090303461A1 - Google Patents' [PAR] These nanoparticles, once excited by light, set up plasmon modes, which, ...