双波长紫外分光光度法同时测定小儿退烧片中对乙酰氨基酚和乙酰水杨酸的含量

建立用双波长等吸收度法同时测定对乙酰氨基酚和乙酰水杨酸含量的方法.应用双波长分光光度法,选择对乙酰氨基酚的等吸收点波长232.5 nm,252.0 nm为乙酰水杨酸的测定波长;同样,选择乙酰水杨酸的等吸收点波长243.5 nm,283.5 nm为对乙酰氨基酚的测定波长.乙酰水杨酸的回归方程为A=0.03218C 0.002 77,r=0.9999;对乙酰氨基酚的回归方程为A=0.05396C 0.00561,r=0.9999.样品中乙酰水杨酸和对乙酰氨基酚相当于标示量的百分含量分别为99.10%和102.37%(n=3).乙酰水杨酸的平均回收率是99.52%,对乙酰氨基酚的平均回收率是99.71%.本法快速、简便,定量准确,用于小儿退烧片中乙酰水杨酸和对乙酰氨基酚含量的同时测定可获得满意的结果.

Simultaneous determination of paracetamol and aspirin in Xiaoer tuishaopian by dual wavelength ultraviolet spectrophotometry

A rapid, inexpensive dual ultraviolet wavelength spectrophotometry was established for the determination of paracetamol and aspirin in Xiaoertuishaopian simultaneously. The wavelengths at isoab-soptive points of paracetamol are 232.5 nm and 252.5 nm and they were accurately selected as the measuring wavelengths for aspirin; the wavelengths at isoabsorptive points of aspirin are 243.5 nm and 283.5 nm and they were accurately selected as the measuring wavelengths for paracetamol. The linear regression equation of aspirin was A = 0.032 18C + 0.002 77 (r = 0.9999); the linear regression equation of paracetamol was A = 0.053 96C + 0.00561 (r = 0.9999). The results showed that the percent of the labeled amount of paracetamol and aspirin were 99.10% and 102.37%(n=3), respectively. The mean recoveries were 99.52% and 99.71% for aspirin and paracertamol. The method was accurate and fast for the determination of paracetamol and aspirin simultaneously in Xiaoertuishaopian.