尿酸UA (Uric Acid)，Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula
C_5 H_4 N_4 O_3
It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the metabolic breakdown of purine nucleotides, and it is a normal component of urine. High blood concentrations of uric acid can lead to gout and are associated with other medical conditions, including diabetes and the formation of ammonium acid urate kidney stones.