Method: Protein in serum sample was precipitaed with saturated ammonium sulfate and then extracted by methanol, pseudoephedrine salicylate was measured by RP- HPLC.

• 方法:血清样品分别用硫酸铵沉淀蛋白,甲醇提取,用反相高效液相色谱法测定伪麻黄碱水杨酸盐。