目的 :研究和测定盐酸普鲁卡因注射液中的降解产物对氨基苯甲酸。方法 :采用离子对HPLC法 ,固定相Luna 5 μC1 8(2 )柱 ;流动相为缓冲液 (0 .0 5mol·L- 1 磷酸二氢钾 ,pH 3.0 ,0 .1%庚烷磺酸钠 ) -甲醇 (77∶2 3) ;流速 1.5ml min ;柱温 35℃ ;检测波长 2 87nm。结果 :对氨基苯甲酸浓度在 2 .0～ 2 0 .0 μg·ml- 1 范围 ,线性关系良好 ,回归方程为C =5 .80 41× 10 - 5 A + 0 .0 782 9,r =0 .9999。回收率为 10 0 .2 % ,RSD =0 .32 %。结论 :本测定方法简便快速 ,结果准确 ,可用于该制剂有关物质检查 Objective: To study and determine the degradation product of p-aminobenzoic acid in procaine hydrochloride injection. Methods: The ion-pair HPLC method was used to immobilize Luna 5 μC 1 8 (2) column. The mobile phase consisted of buffer (0. 05mol·L -1 potassium dihydrogen phosphate, pH 3.0, 0.1% sodium heptanesulfonate ) -methanol (77: 2 3); flow rate 1.5 ml min; column temperature 35 ° C .; detection wavelength 2 87 nm. Results: The linear range of p-aminobenzoic acid was in the range of 2.0-2.0 μg · ml-1. The regression equation was C = 5.80 41 × 10 -5 A +0.782 9, r = 0 .9999. The recovery was 100.2% with RSD = 0.32%. Conclusion: The method is simple and rapid, accurate and can be used for the preparation of the relevant substances