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κ=5.56×105L/（mol.cm）,茶碱浓度在0.10~8.00μg/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0.172μg/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 μg/mL for theophylline with a determination limit of 0.172 μg/L（S/N=3,n=3）.Line regression equation： A=0.064 36 C 0.058 50,correlation coefficient R=0.999 1.