SimplyBlue™ SafeStain from Invitrogen (catalog number LC6060) is a new, ready to use Coomassie G-250 stain that is simple and safe to use for visualizing protein bands in polyacrylamide gels. The manufacturer claims this uniquely formulated stain is fast, sensitive, and safe. The bands develop in minutes; it can detect 7 ng of protein and it requires no hazardous fixatives or destains, just water. SimplyBlue can be used with all polyacrylamide gels (native and non-native) including Tris-Glycine, IEF Zymogram, Tricine, as well as with PVDF membranes. I have found that the SimplyBlue Safestain has been a great alternative to the toxic and flammable Coomassie stains such as R-250, obtained from other manufacturers. It is also easy to use. The reagent is stable for 6 months at room temperature and does not require a flammable cabinet.
A 1 liter bottle containing 1X, ready to use staining solution is used following the instructions on the bottle. A 3.5 L bottle (catalog number LC6065) can also be purchased which uses the same protocol. The basic protocol is to first rinse the gel 3X for 5 minutes with about 100 ml of water and then place gel in about 20 ml of SimplyBlue Safestain for 1 hour, with shaking. Then rinse with about 100 ml of water for one hour, with shaking; a second rinse for another hour may be performed if clearer bands are needed. The manufacturer claims that after just 5 minutes in SimplyBlue Safestain, 1mg of protein can be detected; with additional destaining that 7 ng or less can be detected when using Invitrogen’s premade NuPAGE gels.
There are many advantages to using SimplyBlue that make it a great alternative to traditional Coomassie stains. First of all, the risk of hazardous exposure and odors is removed because it is non-hazardous and does not require the use of other fixatives such as acetic acid or destains. In fact, I obtained its MSDS and it confirms this: it is non-hazardous, non-toxic, non-flammable, and non-corrosive. However, the MSDS sheet does report that it is a mild eye, skin, and respiratory tract irritant so use in a well ventilated area with gloves. It is also a less expensive alternative as there are no HazMat charges, which saves money. Since the used liquid can be disposed of down the drain, waste storage and disposal fees are eliminated.
My experience with SimplyBlue SafeStain has been good. I have used it with Invitrogen’s premade NuPAGE gels (Bis-Tris and Tris-Glycine). SimplyBlue Safestain is specifically designed to use with these gels, but will also work with any other gel. Yes, I have attained fast, sensitive results. Also, I have still attained excellent results even when I left the gel for days in water. The band intensity does not decrease and the water does not evaporate when left for long periods as when using alcohol mixtures. Thus, it is less sensitive to excessive staining or excessive destaining.
The protocol should be followed precisely, however; skipping the 3 water rinses before staining has resulted in a complete lack of staining in my lab. These washes are necessary. However, I have left the gel for longer than 5 minutes for each of the rinses and this has had no deleterious effect.
Overall, the product provides a simple, accurate protein staining method that no other commercially available stain does, and saves both time and money.
Research Associate
Cell Culture, Quality Control Department
Theranostech, Inc