Attention:

Certain features of sigmaaldrich.com will be down for maintenance Saturday afternoon/evening, February 24th starting at 3:00 pm CT until 9:00 pm CT.

Please note that you still have telephone and email access to our local offices. We apologize for any inconvenience.

Fluorescent Labels

The sensitivity and safety (as compared to radioactive methods) of fluorescence has led to an increasing use for the specific labeling of nucleic acids, proteins and other biomolecules. Well-known labels, fluorescein and rhodamine derivatives, are widely used, but suffer from some limitations. A range of improved fluorescent labels has been developed recently. These labels cover the entire range of visible light, reaching from 400 to 820 nm.