Chondroitin Sulfate White or slightly yellow amorphous powder. Tasteless and odorless, hygroscopic. Freely soluble in water; insoluble in organic solvents such as ethanol, acetone and ether. Optical rotation: −25° ~ +35° (c=1, H₂O). Characteristic absorption peaks appear at 725 cm⁻¹, 852 cm⁻¹ and 930 cm⁻¹ in the infrared‑spectrum determination.

Chondroitin Sulfate A, also known as 4‑chondroitin sulfate, is an acid mucopolysaccharide composed of repeating units of (1→4)‑O‑β‑D‑glucopyranuronic acid and (1→3)‑2‑N‑acetylamino‑2‑deoxy‑4‑O‑sulfo‑β‑D‑galactopyranose. It is one of the components of connective‑tissue matrix and serves as the prosthetic group of glycoproteins. The level of Chondroitin Sulfate A changes with age in organisms: its content gradually decreases from birth to old age, while the content of Chondroitin Sulfate C increases.