BDP 581/591 is a borondipyrromethene dye that has relatively long fluorescence lifetime and two photon excitation cross section. It is useful for fluorescence polarization assays. Due to the presence of a diene system, it can react with reactive oxygen species (ROS) with a change of fluorescence. This is the NHS ester derivative for the conjugation with primary and secondary amine groups of proteins, peptides, and other molecules.

Providing storage is as stated on the product vial and the vial is kept tightly sealed, the product can be stored for up to 24 months.
Wherever possible, you should prepare and use solutions on the same day. However, if you need to make up stock solutions in advance, we recommend that you store the solution as aliquots in tightly sealed vials at -20°C. Generally, these will be useable for up to one month. Before use, and prior to opening the vial we recommend that you allow your product to equilibrate to room temperature for at least 1 hour.