The use of staining solution prepared with Coomassie Brilliant Blue R-250 is the fastest approach to stain polyacrylamide protein gels or IEF mini-gels. its relatively high sensitivity. However, when there is no binding, it remains brown. This protocol describes the standard CBR-250 staining method, along with a simple method 100 Pine Street, Suite 1250San Francisco, CA 94111, Coomassie Blue Staining: Definition & Overview, Nucleic Acid and Protein Purification and Extraction Equipment, Coomassie Brilliant Blue is a family of dyes, lower cost and provides better resolution. Its of lower cost and provides better resolution than the G-250 form of the dye. BSAs molecular weight is 66.5 kDa, meaning that 1 mole (610^23) of BSA molecules would weigh 66.5 kg. Alternative Colloidal Coomassie recipes are becoming more and more common because theyre faster & more eco-friendly these forms keep groups of treasure-hunters hanging out outside the gel and gradually send them in until all the treasures found and bound. We get the G-250-based quick stain we use most of thetimepre-made, but we make our own Classic R-250 stain. Speaking of color, a great thing about coomassie stains is that, unlike the DNA gels that use fluorescent dyes we have to stick on a UV tray, http://bit.ly/2zjHH0K. Coomassie Brilliant Blue was first described by scientist Volker Neuhoff and got its name from an African city, Kumasi, which was previously known by the name of Coomassie. The dye helps the visualization of proteins in the form of blue bands. Unlike the common name a company decided to give a product, this is an example of a functional name it describes the chemical makeup in this case three (tri) phenylmethane groups phenyl is a type of resonance-stabilized ring (a ring or atoms that share electrons in a delocalized fashion that makes them good at absorbing light and thus making things look colored) and methyl is a -CH group. At low pH, CBB G-250s brownish, but when it binds proteins, it gets stabilized in blue state so you can tell background brown from treasure blue. If youre kinda nerdy,you might look it up. Speaking of weight, different proteins have different weights because they have different #s of amino acid letters. The dye also assists doctors in retinal surgery. With the right equipment, you can accelerate your R&D and achieve milestones faster! After staining with the dye, you will observe blue bands with a blue background. Analysis of the pheromone signaling pathway by RT-qPCR in the budding yeast Saccharomyces cerevisiae CBB & silver stain are both all protein stains they stain all proteins (though sometimes not equally well). The G-250 form of the stain is used in the staining formulation with other reagents, such as ethanol (or methanol), phosphoric acid, and ammonium sulfate. Coomassie Brilliant Blue has the potential to detect 30-100 ng proteins. The result? Moreover, they should allow flexible staining and destaining time for different lab assays. Coomassie Brilliant Blue staining is an efficient, simple, quick, and affordable protein gel staining technique. Oslo University Hospital is a part of Southern and Eastern Norway Regional Health Authority. No problem the free CBB population can constantly get replenished from colloidal stock rooms (you have a sort of equilibrium between free & colloidal). (and the light tray helps too ). It has a pinwheel-like chemical structure and is characterized as a triphenylmethane dye. CBB can also bind SDS (that detergent we used earlier to solubilize and negatively-charge the proteins) which can mess up results. Its an efficient method to identify the biological sex of the fingerprint as the female samples show higher absorbance than male samples. It also helps that, although we think of CBB as blue, its color depends on its charge. And months. CBB also binds to non-charged protein parts (especially the ring-y (aka aromatic) amino acids like Phe, Tyr, & Trp) generically through Van der waals interactions, whichinvolve shifting around of electrons when molecules get close together. Try not to use a container much larger or much smaller then the gel. Coomassie Brilliant Blue R-250 was first used in 1963 by Fazekas de St. Groth and his colleagues to see proteins separated on a cellulose acetate sheet, after protein gel electrophoresis. It dissolves well in hot water and ethanol but slightly solubilizes in cold water. The non-polar components of the dye bind to the hydrophobic pocket of the protein through van der Waals forces. That makes me mad, so Im going to call it CBB most of the time. The staining chemistry of these protein dyes is based on their binding with the protein and the matrix. And those clumps really are dissolved(they dont come undone when you let the solution sit). Under the conditions of the staining solution it has overallcharge (anionic), so it binds (reversibly) to-charged parts of proteins (basic amino acids like Arg, Lys, & His) through electrostatic interactions (opposites attracting). The dye transfers a free electron to the groups of the proteins that can be ionized. Below are two lab applications that are routinely performed and involve the use of Coomassie Brilliant Blue stain along with other reagents that are required to prepare the staining solutions. CBB is colorimetric the readout is color, so the results are literally right there tosee, no special equipment required (unless you count theeye, which is a pretty spectacular tool!) However, acquiring each piece of such equipment might make you break your bank. Lets take a closer look at our treasure hunter, Coomassie Brilliant Blue (CBB). Browse your leasing options today! The separated proteins can be detected by using either Coomassie Brilliant Blue, fluorescent, or silver staining methods. Thus, you can see the bands even without destaining. STAIN send in the treasure hunters stick the gel in a bath of dye the dye enters, latches onto the protein and gets stuck too (this steps often combined w/the fixing step), DESTAIN call off the hunt get the treasure-less treasure hunters to leave so you can better see where the treasure-full ones are (some rapid stains have low backgrounds & you just destain in water, letting the dye diffuse out, but some methods use more complex destaining), water wash -> get buffer components to diffuse out of gel -> start with a clean slate, fixation/stain -> immerse gel in a staining solution (CBB + methanol (MeOH) + acetic acid (AcOH)) (some more eco-friendly methods use ethanol), we dissolve CBB in a MeOH/AcOH solution to combine the fixation & staining steps. The transfer of electrons to protein disrupts its native structure and exposes its hydrophobic pockets. This is done by using a destaining solution, which takes approximately 10 minutes to overnight to remove excess stain and produce bands with clear background. More on moles here: http://bit.ly/solutionconcentrations. There are also fluorescent all protein stains. Could that be a massive protein I see? The technique is preferable, simpler, and easier than the ninhydrin chemical assay, which requires an assay preparation and involves the use of a cascade of enzymes in the process. note: It takes a really, really long time for the CBB powder to dissolve, so let it stir for several hours on a magnetic stir plate and then filter through a coffee filter to remove any undissolved stuff, fixation: protein precipitates so is trapped in the gel matrix, when dye meets protein -> dye binds -> gets trapped because the proteins trapped. This binding imparts overall negative charges to the proteins and facilitates their separation from SDS-PAGE gels based on their molecular weight. The protocol utilizes Coomassie Brilliant Blue R-250 in a methanol/acetic acid solution and stains proteins by gentle shaking at room temperature. Coomassie Brilliant Blue is available in three forms: cationic (red), neutral (green in color), and anionic (blue). But the key thing here is that bigger proteins have more to love in CBBs eyes they offer more binding sites and thus will more BSA per protein molecule than a smaller protein. This protocol was adapted from Peptide Mapping and Sequence Analysis of Gel-Resolved Proteins, Chapter 7, in, Zinc/Imidazole Procedure for Visualization of Proteins in Gels by Negative Staining, Variations of Staining Sodium Dodecyl SulfatePolyacrylamide Gels with Coomassie Brilliant Blue, Alert me when Updates/Comments are published. Excedr allows labs of all sizes to outfit their labs with the right pieces of equipment. DOI 10.3390/ijms23031293, PubMed 35163213, Department of Molecular Cell Biology, Institute for Cancer ResearchThe Norwegian Radium Hospital, Montebello, N-0379 Oslo, NorwayTelephone +47 22 78 19 82 (Enserink), +47 22 78 12 69 (Dept. Figure: The structure of the Coomassie Brilliant Blue G-250. The goal here isnt to purify the proteins, instead the goal is just to see whats there. The G in the name denotes the greenish tint of the dye. The ability of Coomassie Brilliant Blue to form a complex with proteins enables its use in Bradford assay for fingerprint analysis. The bigger (longer) proteins get tangled up more, so they travel slower and have progressed less (so higher up on gel) when you turn off the power. And that keratin-binding ability which makes itgood at dyeing woolalso makes itgoodat dying your skin so wear gloves & avoid splashing. Apart from its uses in protein visualization, the dye is also used to determine the concentration of protein in the sample and in forensic labs to identify the sex of the given fingerprint. Our leasing program helps you to direct your focus to your experiments and invest the rest of your money in operating your lab and achieving quality results. Webmaster for research pages: Trond Olav Berg. Terms of Service. Another approach is procuring your desired equipment on lease, using Excedrs leasing solution. Both are blue, but Rs more reddish & Gs more greenish (although the color depends on the pH and whether and what its bound to which is why it can be used to measure protein concentrations in something called a Bradford assay http://bit.ly/bradforduv ). Polyacrylamide (prepared by mixing acrylamide and bisacrylamide) gel electrophoresis is a technique to separate proteins based on their molecular weight for molecular biology experiments and protein analysis. Coomassie Brilliant Blue is a widely used protein staining technique. It works on the principle of binding the dye with the protein molecules. And months. The colloids are too big toenter thegel so you dont overstain.BUT the FREE molecules can come & go from the gel as they please and they do, just as before, except now theyre at alower concentration. The dye has a chemical formula C47H50N3NaO7S2 (Sodium salt) and a molar mass of 3 g/mol. Instead of flooding the gel with dye (like the classical method) you supply a steady, mild flow of CBB moleculesenough to quench the proteins thirst, but not so much that it can stick to the gel. During the complex formation of Coomassie Brilliant Blue with the protein, the reaction that occurs includes the following steps: The best commercial coomassie dyes are the ones that have high sensitivity, superior reproducibility, and low background. The advanced equipment ensures the productivity of your lab and the validation of produced data. (though the protein will be stuck in place through chemical-induced clumping as well see). CBBs protein-binding ability also makes ita goodwool dye because wools chock full of a protein called keratin. Its used to stain protein gels and in Bradford assay. You can think of the SDS-PAGE gels matrix as maze with protein treasure hidden throughout. GEL ELECTROPHORESIS separate proteins by size by unfolding them, coating them in negatively-charged detergent (SDS) & using that negative charge to motivate them to travel through a polyacrylamide gel mesh towards a positive charge. So we need to get the treasure to stay put the FIXATION step uses an alcohol and/or acid to make the protein to precipitate (clump up) so it gets stuck in place so our treasure-hunting dye can find it. Its a really simple recipe only 4 ingredients: water, acetic acid (AcOH), methanol (MeOH), & CBB but it takes a while to prepare more here: http://bit.ly/2QJNwLy. When it finds protein treasure, it latches on. The SUMO stress response in transcriptional regulation: Causal relationships or secondary bystander effects? So how does it stick to our protein but not the gel? Coomassie was initially used to market a wide range of wool dyes, with CBB first made in 1913 & first used to stain proteins in 1960s. The ionic interaction and complex formation through the reaction allow the visualization of the protein bands separated in protein gel. But proteins are invisible to the naked eye, so we need some sort of dye in order to protein-spy. Analysis of the pheromone signaling pathway by RT-qPCR in the budding yeast, Cell Cycle-Dependent Transcription: The Cyclin Dependent Kinase Cdk1 Is a Direct Regulator of Basal Transcription Machineries, Southern and Eastern Norway Regional Health Authority. The Coomassie Brilliant Blue R-250 is another form of disulfonated triphenylmethane compound. Dye-ing to know more about the dye itself? However, during the staining procedure, the gel matrix is also stained. note: those side chains arent always positive, but we stain the gel in acidic conditions, where theyre more likely to be more here: http://bit.ly/30qzHH6. These interactions are individually weak but they add up(theyre what allowgeckosto walk up walls!). Coomassie Brilliant Blue G-250 (or colloidal coomassie blue) contains two methyl groups, which are absent in the R-250 version of the dye. This is because in order to find tiny treasure you unleash a ton of treasure hunters that race in from the dye bath, where theres a high concentration of dye, to the pores of the gel where theres more room and hopefully protein! Remove SDS-PAGE gel from glass and rinse once in ddH2O in a suitable container with a lid. And where we dont want it is anywhere in the gel there isnt any protein. But the really cool fluorescent stains only stain specifically-modified proteins like glycoproteins (which have sugar chains added) or phosphoproteins (which have phosphate groups added), https://doi.org/10.1586/14789450.1.4.381 https://sciwri.club/archives/3483 https://www.nationaldiagnostics.com/electrophoresis/article/staining-protein-gels-coomassie-blue, more on topics mentioned (& others)#365DaysOfScienceAll (with topics listed)http://bit.ly/2OllAB0, Your email address will not be published. We commonly talk about protein weights in terms of molecular weight (MW) and units of kiloDaltons (kDa). Some of the areas that involve the use of the dye are mentioned below. We can separate proteins by size by sending them traveling through an SDS-PAGE gel, but in order to find our protein treasure we need to send in some treasure hunters. It can be routinely used in proteomics-related studies, such as mass spectrometry, SDS-PAGE, and IEF, to detect approximately 0.10.5 g proteins. The background noise should also be reduced to make the bands easier to visualize. The R in the name denotes the reddish tint of the dye. You must also know that the name Coomassie is a registered trademark of Imperial Chemical Industries. http://bit.ly/bradforduv. When [dye outside gel] = [dye inside gel] youve reached , the stain cant go down the drain instead we collect it in hazardous waste containers that our environmental health & safety (EH & S) workers dispose of properly, at the start, theres high CBB in gel, NO CBB in bath -> CBB diffuses out of gel into bath, this makes CBB concentration in bath increase -> less of a difference between gel & bath -> CBB diffuses more slowly. CBB has sulfuric acid groups that can benegative or neutral depending on pH. So weve been experimenting with a few other formulations but they seem to start bluer and give higher background. So how do you get enough to stain the protein? Coomassie is actually a trademark name owned by a company that no longer even makes it & a town name (modern-day Kumasi, Ghana). Where we want it is stuck to our protein (which is itself stuck in our gel). In the presence of an acidic condition, the red coomassie dye converts to blue when it binds with the protein. you might then tell other people about it! Copyright 2022 by Cold Spring Harbor Laboratory Press. note: this post is refurbished from September 2019, about 300 SDS-PAGEs ago (literally, not exaggerating today I ran my 732nd, 733rd, & 734th!) Executing experiments like electrophoresis and mass spectrometry are made easier with high-throughput equipment. Based on their properties, molecular characteristics, staining ability, and sensitivity, Coomassie Brilliant Blue is of two types: Coomassie Brilliant Blue G-250 and Coomassie Brilliant Blue R-250. CBB wasnt discovered or produced there, nopea British company thought naming their product after the capital of the Ashanti empire they recently conquered would begoodbusiness strategy. The SUMO stress response in transcriptional regulation: Causal relationships or secondary bystander effects? In this article, we will briefly cover a brief on types of Coomassie Brilliant Blue, their applications in lab assays, and industrial areas that extensively utilize the dye for a myriad of purposes. But theyll keep snooping around even if theres no protein left to find because you have high concentrations of free dye inside and outside the gel. More here: FIX trap the treasure the gel has to allow proteins to move when you want them to, but not too easily Ideally theyd only move when powers on, but molecules like to move and if they can they will so (especially the small ones) can start wandering off even when the powers off). Grad school, thesis, & postdoc-related posts, https://www.nationaldiagnostics.com/electrophoresis/article/staining-protein-gels-coomassie-blue. The treatment has been found effective in lab rats, however, their efficacy on humans is still unknown. R-250 ismoresensitive , but G-250 can be made into forms that producelowerbackground, withfaster protocols. SDS-PAGE (Sodium Dodecyl Sulfate PolyAcrylamide Gel Electrophoresis) is a technique we use to separate proteins in a mixture by size (well, length) using electricity to send the proteins through a gel mesh. Coomassie Brilliant Blue is a family of dyes that are routinely used in labs for protein staining protocols, performed after SDS-PAGE or polyacrylamide gel electrophoresis. Coomassie Brilliant Blue is one of the widely used stains in protein estimation assays, such as the Bradford assay. 1. video added 3/15/22. The dye forms a complex with the basic amino acid residue of the proteins, including arginine, histidine, tyrosine, and lysine for their visualization. Get your customized leasing solution now. This leads to an overall treasure-hunting scheme of: As I alluded to, there are lots of different formulations including Classic Coomassie which has really eager treasure-hunters that can find tiny amounts of treasure but are also fools-gold-happy its super sensitive and eventually gives you nice crisp bands, but takes a lot of destaining to reveal them. on a mission to make biochemistry fun and accessible to all. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Coomassie Brilliant Blue SDS-PAGE staining, Troubleshooting recombinant protein expression. The dye travels randomly through the gel maze by diffusion (the molecules move around randomly, ricocheting off the things they run into with the NET RESULT that they move from areas of high concentration to areas of low concentration). Excedr can help your lab get the technology and equipment it deserves. Excedrs leasing solution allows you to save your time on purchasing each piece of equipment, and money by preventing the requirement of upfront payments and covering the equipments repair and maintenance costs. However, its sensitivity depends on the type of stain (Coomassie Brilliant Blue G-250 and Coomassie Brilliant blue R-250) used in the staining method. And the one we use most often is a dye called Coomassie Brilliant Blue (CBB), either in the classical way or in the form of faster colloidal stains (often advertised as some trademarked version of instant blue). Proteins with unusually high proportions of ring-y amino acids tend to stain better. Enserink JM (2022) And since the dyes blue it tells us where the protein is. Copyright 2022 by Cold Spring Harbor Laboratory Press. for preparing stained gels for long-term storage. But its really hard to find treasure thats trying to escape! So you want to wash your gel in water before staining to remove the SDS. That stains been on back-order for months. We also have to watch out for overly-eager treasure hunters that latch onto fools gold (stain the gel itself) causing high background. Most scientific reagents have boring(though descriptive) names, so you might wonder how Coomassie Brilliant Blue (CBB) got its name. Therefore, to remove the background color, a destaining solution is applied to the gel for better visualization of blue protein bands on a clear background. where theres not any protein, the dye still fills the pores of the gel, but its not trapped (it can flow in and out but at this point its flowing mainly in because the dye concentration ([dye]is higher in the stain than in the gel). Your email address will not be published. Int J Mol Sci, 23 (3) Consider leasing through Excedr to save your lab time and money. As you can hopefully see from the pics, Classic CBB initially stains your whole gel blue so you cant see the bands until you destain it and de-blue whats not supposed to be blue. Cell Cycle-Dependent Transcription: The Cyclin Dependent Kinase Cdk1 Is a Direct Regulator of Basal Transcription Machineries The most commonly used dye for visualizing proteins in SDS-PAGE gels is Coomassie Brilliant Blue R250 (CBR-250) because of Another colorimetric protein stain is silver staining, which is more sensitive, but also more finicky. But none of that really matters if the dyes not where you want it and only where you want it. Bioessays, 44 (7), e2200065 It offers equipment ranging from analytical equipment, and clinical instruments, to biotech and general biology equipment. An example is BSA (bovine serum albumin), which recruits twice as many treasure hunters per weight of protein than your average protein. At least, the stain we used to get was more brown-y. Moreover, in western blot analysis, the dye is used as a loading control staining method, where its employed as an anionic pre-antibody stain. 250 was originally a purity/strength indicator. Here, theres no directionality to movement of things, so the dye will move wherever the heck it wants! Coomassie Brilliant Blue is a part of many experimental studies in labs, including treating spinal injuries. But Colloidal CBB doesnt require as much destaining (though it helps make the bands crisper) because, instead of sending in a ton of treasure hunters you then have to kick out, it has groups of hunters hang out outside the gel and only go in as needed.