20278
20279
PIER20278EA
182
EUR
InStock
PIER20278
PIER20279
Bleu brillant de Coomassie® R250
Bleu brillant de Coomassie® R250
Thermo Scientific Pierce coomassie brilliant blue dyes are composed of one of the most common forms of coomassie dye, which is a key component of various colorimetric protein gel stains. Coomassie R-250 and G-250 dyes are two chemical forms of a disulphonated triphenylmethane compound that is commonly used as the basis of stains for detection of proteins in gel electrophoresis and bradford-type assay reagents for protein quantitation. The R-250 (red-tinted) form lacks two methyl groups that are present in the G-250 (green-tinted) form, which is also called colloidal coomassie dye.
- Coomassie gel stains and protein assay reagents are formulated as very acidic solutions in 25 to 50% methanol
- In acidic conditions, the dye binds to proteins primarily through basic amino acids (primarily arginine, lysine, and histidine), and the number of coomassie dye ligands bound to each protein molecule is approximately proportional to the number of positive charges found on the protein
- Protein binding causes the dye to change from reddish-brown to bright blue (absorption maximum equals 595 nm)
- Its detection location is gel, solution, blot
Features include: Easy detection and mdash develops intensely coloured complexes with proteins high sensitivity and mdash can determine as little as 0,5 microg/cm² of protein present in a gel matrix reversible staining and mdash anion of coomassie brilliant blue dye formed in the acidic staining medium combines with the protonated amino groups of proteins by electrostatic interaction resulting complex is reversible under proper conditions differentiation between bound and unbound dye and mdash when dissolved in 0.01 M citrate buffer at pH 3,0, has an absorption maximum at 555 nm protein-dye complex is characterised by a peak slightly broader than that of free dye with a maximum at 549 nm for research use only. Not for use in diagnostic procedures.