Gram’s safranin solution
SIAL/94635 - for microscopy
Synonym: Safranin T solution
CAS Number: 477-73-6
Empirical Formula (Hill Notation): C20H19ClN4
Molecular Weight: 350.84
MDL Number: MFCD00011759
Linear Formula: C20H19ClN4
Product Type: Chemical
| εmax | 4.0 at 532 nm in 50% ethanol |
| antibiotic activity spectrum | Gram-negative bacteria |
| Gram-positive bacteria | |
| application(s) | diagnostic assay manufacturing hematology histology |
| color | red to very dark red |
| composition | ethanol, 10% |
| density | 0.986 g/mL at 20 °C |
| form | liquid |
| grade | for microscopy |
| InChI | 1S/C20H18N4.ClH/c1-12-8-1 |
| InChI key | OARRHUQTFTUEOS-UHFFFAOYSA |
| Quality Level | 100  |
| refractive index | n |
| shelf life | limited shelf life, expiry date on the label |
| SMILES string | [Cl-].Cc1cc2nc3cc(C)c(N)c |
| solubility | water: soluble at 20 °C |
| storage temp. | room temp |
| technique(s) | microbe id | staining: suitable |
| Application: | Gram’s safranin solution has been used in the following applications:• as a non-toxic replacement for crystal violet for the quantification of biofilm formation • to develop a hyaluronic acid visualization method • to study improved β-lactam susceptibility against biofilm-embedded staphylococcus aureus by 2-aminothiazole |
| Features and Benefits: | • Ready-to-use solution. • Modified and designed in such a way that staining can be carried out in staining cells, on the staining rack, and in automated staining systems. |
| General description: | Gram’s safranin solution, also known as Safranin T or Basic Red 2, is a ready-to-use staining solution that comprises 10% safranin in ethanol. Safranin is a basic, cationic, azine dye containing a planar, diaminophenazine chromophore, with a phenyl substituent attached to a ring nitrogen. The trimethyl cationic form of safranine is lipophilic, whereas the dimethyl forms are weakly hydrophilic. It is most notably used in bacteriology as a counterstain in Gram staining to differentiate between Gram-positive and Gram-negative bacteria. |
| Principle: | Gram staining enables the differentiation of bacteria into Gram-positive and Gram-negative. The mureine structure of the bacterial cell wall is the basis of the color affinity. Bacteria are first stained with crystal violet, and then with iodine solution, which forms a dye-iodine complex. This complex is retained in the multi-layer mureine structure of the cell wall of Gram-positive bacteria after decolorization, imparting a blue-violet color. The cell wall of Gram-negative bacteria comprises a single-layered murein structure that does not retain the dye-iodine complex, allowing the uptake of safranine counterstain, and imparting a pink-red color. |
| Symbol |  GHS02 |
| Signal word | Warning |
| Hazard statements | H226 |
| Precautionary statements | P210 |
| Risk Statements | 10 |
| RIDADR | NA 1993 / PGIII |
| WGK Germany | WGK 2 |
| Flash Point(F) | 114.8 °F |
| Flash Point(C) | 46 °C |
| Density | 0.986 g/mL at 20 °C |
| Refractive Index | n |
| Storage Temp. | room temp |
| UNSPSC | 12171500 |