- Biotin (N-Terminal, w or w/o Ahx)
- Biotin (via side chain of Lys)
- FITC/5-FAM (N-Terminal, w or w/o Ahx)
- FITC/5-FAM (C-Terminal, via side chain of Lys)
- Dansyl (N-Terminal, w or w/o Ahx)
- TAMRA (N-Terminal)
- TAMRA (C-Terminal, via side chain of Lys)
- MCA (N-Terminal)
- HYNIC (N-Terminal)
- DTPA (N-Terminal)
