Linear Alkyl Benzene Sulphonic Acid (LABSA) Dodecyl Benzene Sulphonic Acid (DBSA), or simply Sulphonic Acid are few of the several names given to a type of organic acid that can be represented by the general formula R–SO2 –OH, where ‘R’ is usually a hydrocarbon side chain. LABSA or sulphonic acid is the largest-volume synthetic surfactant manufactured because of its relatively low cost and good performance. Sulphonic acids have the unique tendency to bind to proteins and carbohydrates tightly; most “washable” dyes are sulphonic acids (or have the functional sulfonyl group in them) for this reason. Sulphonic acids and their salts (sulphonates) are used extensively in such diverse products like detergents, sulfa drugs, anion exchange resins for water purification, dyes, emulsifiers, etc. Sulphonic acid is soluble in water and is corrosive to metal and tissue.