Cy3B maleimide is a mono-reactive dye containing maleimide group, which can selectively and efficiently attach Cyanine3 fluorophore (an analog of Cy3) to proteins and peptides containing cysteine residues, as well as to other thiolated molecules (such as thiol-containing oligonucleotides). Cy3B is an improved version of Cy3 dyes with significantly increased fluorescence quantum yield and photostability.

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.