Rhodamine 110 (Rh110)-labelled peptides from Anaspec are used in the study of a number of protease activity, such as cysteine aspartate-specific proteases and serine proteases.
Rh110 contains two amino groups available for conjugation to the C-terminal end of a peptide or amino acid.
Protease cleavage of the non-fluorescent bis-substituted Rh110 peptide derivatives result in mono-substituted Rh110 and free Rh110, both of which are fluorescent.
Fluorescence intensity can therefore be correlated to protease activity.
Rh110 conjugated to charged amino acids is generally cell permeable.
As a result, these substrates can be used in intact cells for applications such as flow cytometry.
Rhodamine-labelled peptides are claimed to offer several advantages over AFC- or AMC-labelled peptides in that Rh110 emits in the green range (Ex/Em=501/527nm), while AMC (Ex/Em=340/440nm) and AFC (Ex/Em=370/500nm) emit in the blue range.
Auto-fluorescence interference from cellular components is minimal, making the substrates more sensitive.
Rh110 peptide conjugates are not pH dependent.
