5-Sulpho Salicylic Acid is a sulphonated derivative of Salicylic Acid. It’s a white crystalline powder that is soluble in water, alcohol, and ether. It’s stable at room temperature and should be stored in well-closed, light-protected containers. This acid is primarily used in urine tests to determine urine protein content. Its strong association with a range of metals makes it a useful metal scavenger.