• The faster, more sensitive colloidal Coomassie Blue stain
  for visualizing PAGE protein bands.
• Bands appear in 15 minutes
• Safe, nonhazardous solution formula

ProtoStain Blue is a fast 'ready-to-use premixed' colloidal Coomassie Blue G-250 solution that is a safer more sensitive method for detecting proteins on electrophoresis gels.   Bands begin to appear in only 15 minutes, and ProtoStain Blue has the ability to detect down to 1ng denatured BSA.

Most Sensitive Colloidal Colloidal Coomassie Stain on the market !
ProtoStain Blue is ready-to-use, safe and nonhazardous, containing no methanol, acetic acid or phosphoric acid.  Where local regulations permit, ProtoStain Blue can be poured down the drain, as it is not classified as a hazardous waste according to United States Title 40 Code of Federations (40 CFR 261.24 (a)) and EEC Directive 79/831/EEC Annex VII, JIS K 3363-1967  (always consult local and state regulations before disposing of any laboratory reagents).

The ProtoStain Blue stain formulation is compatible with all polyacrylamide gel types, and produces lower background staining than competing stains without requiring extensive water destaining to produce a crystal clear background. 

Standard protocol is 4-5 hours and is available to view on request. Note that this protocol is optimized for a 075mm thick gel. Thicker gels require longer water washes. There is also a Rapid protocol (60 minutes) for fast staining. 20ng of denatured BSA can be detected after 10 minutes destaining in water. Less than 5ng can be detected after overnight incubation in water, due to a combination of bands binding residual dye and the production of a crystal clear background. A Mass Spectroscopy protocol is also listed where gels stained with ProtoStain Blue can be destained for in-gel tryptic digest with 25-100nM ammonium bicarbonate/50%acetonitrile.

Protocols available - Inquire at 1-800-245-5774 or sales@e-LSPI.com.

Frequently asked questions:

Is ProtoStain Blue quantitative?  ProtoStain Blue gave a linear OD with protein concentration in a test covering three orders of magnitude.
Is ProtoStain Blue compatible with mass spec?  ProtoStain Blue is compatible with mass spectroscopy.
Can the stain be reused?  Reusing the stain is not recommended. Components of the gel and running buffers reduce staining ability over time.
Does ProtoStain Blue work better with some gels than others? (There are many typs of SDS-PAGE gels, from traditional to long-life precast gels.)  No. ProtoStain Blue performs comparably on all gel types tested. Thicker gels take longer to stain while lower percentage gels initially have higher background staining than higher percentage ones.
Can ProtoStain Blue be poured down the drain?  ProtoStain Blue contains components that are not considered hazardous waste (as defined by United States Title 40 Code of Federal Regulations (40 DFR 26124 (a)) as well as EEC Directive 79/83/EEC Annex VII, JIS K 3363-1967). Observe all local regulations.
Is ProtoStain Blue compatible with gel-drying solutions?  Gels can be incubated in drying solutions containing up to 20% ethanol for up to 20 minutes without loss of staining intensity. Longer incubation will eventually lead to destaining of bands.
Can proteins be stained with ProtoStain Blue that are transferred to membranes?  ProtoStain Blue is not recommended for staining proteins on membranes because of the high background produced.
How does ProtoStain Blue compare with Coomassie R-250 stains?  ProtoStain Blue is faster, more sensitive, safer, and costs less. Furthermore, the ProtoStain Blue stain solution may be deposed as nonhazardous waste in most locations.
Is the washing step before staining necessary?  The washing steps remove gel components that inhibit staining or may cause background staining.
I loaded 5ng of protein in a lane but I cannot detect it with ProtoStain Blue. Is something wrong?  The 1ng sensitivity reported is for gels containing denatured BSA. You may achieve higher or lower staining sensitivities depending on the protein being stained.
Can I stain isoelectric focusing gels with ProtoStain Blue?  Yes. IEF gels can be stained with ProtoStain Blue. Carrier ampholytes in the gel may cause high backgrounds. To avoid this, the gels must be fixed in TCA before staining. Refer to manufacturer instructions.
Can I store a gel stained in ProtoStain Blue without drying it?  Gels stained in ProtoStain Blue can be stored in water for several days without loosing sensitivity.
Can I leave my gel in ProtoStain Blue over the weekend?  Yes. You can leave the gel in the stain over the weekend with only a slight increase in the background.
There is a precipitate at the bottom of the bottle (when I received it and after it has been on he shelf for awhile). Is the normal?  ProtoStain Blue contains colloidal particles that will normally settle out on standing. Gently invert the bottle several times to resuspend particles before use.