These light-emitting types of dyes like rhodamine & aniline blue are used to label proteins
... Two types of covalently attached fluorescent probes have been used 
in... [DOC] [TLE] Classic Reactive Fluorescent Labeling Dyes & Their ... - ResearchGate [PAR] Reactive fluorescent dyes are widely used to modify amino acids, peptides, 
proteins (in ... reagents are currently used to label biopolymers: succinimidyl 
esters (SE), ...