紫外-可见光度法测定茶碱缓释片中茶碱的研究
The Determination of Theophylline in Sustained-Release Tablet with the UV-Vis Spectrophotometry

在H2BO3-Na2B4O7缓冲溶液中,甲酚红同茶碱会发生诱导荷移反应,使其吸收光谱发生变化.以十二烷基磺酸钠作增敏剂,常温下显色20 min,茶碱与甲酚红形成2∶1型络合物,其λmax=570 nm,摩尔吸光系数 k=5.56×105 L/(mol.cm),茶碱浓度在0.10～8.00 μg/mL范围内符合比尔定律,线性回归方程为A=0.064 36C-0.058 50,相关系数R=0.999 1,根据信噪比确定的检测限(S/N=3,n=3)为0.172 μg/mL.该方法简单易行,准确度、灵敏度高,适用于快速、大批量地分析茶碱缓释片中的茶碱.
Using sodium dodecyl sulfate(SDS)for the synergistic agent, placed at 20 minutes, based on the reaction of theophylline and cresol red, a simple, rapid and sensitive spectrophotometric method was described for the determination of theophylline, The complex has a maximum absorption at 570 nm, and its molar absorptivity is 5.56×105 L/(mol?cm), the method is high sensitivity and selectivity and Beer′s law is obeyed in the range of 0.10~8.00 ?g/mL for theophylline with a determination limit of 0.172 ?g/L (S/N = 3, n = 3).Line regression equation: A = 0.064 36 C?0.058 50, correlation coefficient R=0.999 1