Cresol Red
CAS Number: 1733-12-6
Molecular Weight: 382.43
MDL number: MFCD00005878
EC Index Number: 217-064-2
General description
Cresol Red, also known as o-cresol red, belongs to the phthalein and sulphonphthalein group of dyes. Cresol red changes color from orange to yellow at pH between 0.2-1.8 and yellow to violet at pH between 7.0-8.8. In alkaline solutions, cresol red is present as a hydrophilic dianion. The dianion is small and is violet in color, possessing a larger conjugated system than the yellow hydroxyquinone.
Application
Cresol Red is a widely used pH indicator for routine pH assessments like microbial culture media preparations. In addition, Cresol red is a suitable constituent of PCR reagent systems. Cresol Red is used as a tracking dye in DNA, RNA (agarose), and protein (polyacrylamide) electrophoresis.
| grade | indicator grade |
| Quality Level | 200 |
| form | powder or crystals |
| composition | Dye content, 95% |
| technique(s) | titration: suitable |
| pH | 7.2-8.8, yellow to red |
| useful pH range | 1.8-2.0, orange to yellow(acid)
7.0-8.8, yellow to violet(alkaline) |
| mp | 290 °C |
| density | 0.998 g/cm3 |
| λmax | 367 nm (2nd) 570 nm |
| application(s) | diagnostic assay manufacturing
hematology histology |
| storage temp. | room temp |
| SMILES string | Cc1cc(ccc1O)C2(OS(=O)(=O)c3ccccc23)c4ccc(O)c(C)c4 |
| InChI | 1S/C21H18O5S/c1-13-11-15(7-9-18(13)22)21(16-8-10-19(23)14(2)12-16)17-5-3-4-6-20(17)27(24,25)26-21/h3-12,22-23H,1-2H3 |
| InChI key | OBRMNDMBJQTZHV-UHFFFAOYSA-N |
