Store freeze-dried powder at 2-8°C. When ready to use, rehydrate with indicated volume of d. water and centrifuge if not clear. Product is stable for about 6 weeks at 2-8°C as an undiluted liquid. Prepare working dilution fresh each day. For extended storage after rehydration, add an equal volume of glycerol (ACS grade or better) for a final concentration of 50%, and store at -20°C as a liquid. Note: after the addition of glycerol, the concentration of protein and buffer salts is one-half of the original. Alternatively, aliquot and freeze the product at -70°C or below in the absence of glycerol. Avoid repeated freezing and thawing.Expiration date: one year from date of rehydration. However, the expiration date may be extended if the product is stored according to the recommendation and the test results are acceptable for its intended use.

Cyanine Cy™2

Cy2 conjugates have maximum absorption/excitation at 492 nm and fluoresce with a peak around 510 nm in the green region of the visible spectrum like FITC conjugates (520 nm), but they are more photostable and less sensitive to pH changes than FITC. However, for mounting in aqueous media we recommend Alexa Fluor® 488 as the preferred green-fluorescing dye because it is brighter and more photostable than Cy2, FITC, and DyLight 488. A further disadvantage of using Cy2 with aqueous mounting media is its sensitivity to p-phenylenediamine, an anti-fading agent found in some commercial mounting media, which results in weak and diffused fluorescence after storage of stained slides. The main advantage of Cy2 conjugates is increased fluorescence in plastic mounting media.