Some of our large volume light-sensitive products are packaged in amber bottles or amber glass vials, which are easy to handle and protect the products from light. However, amber micro packaging vials (0.5 mL or 2 mL) make it very difficult to see small quantities of dye when preparing solutions or pipetting. Therefore, we only package photoreactive dyes like PMA or PMAxx™ in amber micro packaging vials. Some of our reactive dyes are packaged in transparent vials, then sealed inside a moisture-resistant foil bag, which also will protect them from light.
Other fluorescent dyes in transparent vials should stored in the dark for long term storage. It’s fine to store dye vials uncovered in a windowless refrigerator or freezer with an automatic light shut-off. If dyes will be stored in a glass-front (deli-style) refrigerator, walk-in refrigerator/freezer, or at room temperature with constant light exposure, they should stored in a non-transparent box (like a white cardboard freezer box), in a closed drawer, in a black plastic bag, or covered with aluminum foil.
Fluorescent dyes generally are not sensitive to brief light exposure while they are being handled on the bench during an experiment. To be on the safe side, we usually loosely cover tube racks with a piece of foil if the dye vials are going to be out on the bench for more than 30 minutes or so. But most dyes are stable enough that even accidentally leaving them on the bench for a day will not affect performance. When handling photoreactive dyes like EMA, PMA, or PMAxx, we take the extra precaution of dimming the lights.View more FAQs