5-Sulfosalicylic acid dihydrate
| Formula (Hill) | C7H6O6S*2H2O |
| Density: | 0.8g/cm3 (20 °C) |
| Molar mass: | 254.22g/mol |
| Bulk density: | ~310 kg/m3 |
| CAS Number | 6965-83-3 |
| HS Code | 29182910 |
| EC Number: | 202-555-6 |
| Storage : | at+15 Oc to+25 °C |
| SDS | available |
| R phrase: | R 36/38 |
| S phrase | S 26 |
| Odour: | Slightly pungent |
| Form: | Crystals |
| Color: | White to grey |
| pH value: | <0.5 (200 g/l 20 °C) |
| Solubility in water: | (20 °C) freely soluble |
| Solubility in ethanol: | (20 °C) freely soluble |
| Flash point | ~150 °C |
| Melting point: | 105-109 °C |
| Thermal decomposition: | ~200 °C |
| Assay | ≥ | 99 | % |
| Description | Conforms | ||
| Solubility | Conforms | ||
| Identification | Conforms | ||
| Salicylic acid | Conforms | ||
| Water | ≤ | 15 | % |
| Heavy metals | ≤ | 0/001 | % |
| Melting Point | 105 – 109 | °C |
5‑Sulfosalicylic acid dihydrate is an aromatic sulfonic acid compound derived from salicylic acid. It appears as a white crystalline solid and is primarily used in clinical laboratories for detecting proteins in biological fluids such as urine.
🏭⚗️ Production
This compound is synthesized by introducing a sulfonic acid group to the structure of salicylic acid, resulting in a highly acidic molecule known as 2-hydroxy-5-sulfobenzoic acid. The dihydrate form contains two molecules of water of crystallization.
🔬 Properties
5‑Sulfosalicylic acid dihydrate has the molecular formula C₇H₆O₆S·2H₂O and a molar mass of approximately 254.2 g/mol. It is a white crystalline substance with a melting point around 120 °C. The compound is highly soluble in water and has strong acidic properties due to the presence of both carboxylic and sulfonic acid groups.
🧪 Applications
This compound is commonly used in protein precipitation tests, particularly for detecting proteinuria in clinical diagnostics. It causes proteins to precipitate when added to biological fluids, allowing for visual or quantitative assessment. Additionally, it is used in certain metal treatments such as integral colour anodizing and serves as a component in specific biochemical assays, including siderophore detection using the CAS method.
⚠️ Safety
5‑Sulfosalicylic acid dihydrate should be handled with care, as it is a corrosive substance that can cause skin and eye irritation. Appropriate protective equipment such as gloves and goggles should be worn, and the compound should be used in a well-ventilated environment.
