Elsayed M A, Belal S F, Elwalily A F, Abdine H
J Assoc Off Anal Chem. 1979 May;62(3):533-7.
Two spectrophotometric methods, Glenn's method of orthogonal function and the basic dye method, are described for determing tolbutamide in tablets without interference from the tablet excipients. In Glenn's method, the absorbance of tolbutamide in 95% ethanol is measured in the vicinity of 250--270 nm at 4 nm intervals and the p2 coefficient is calculated. The coefficient is linearly related to concentration within a range of 0.1--0.4 mg/mL. Tolbutamide gives a complex of a ratio 1:1 with basic dye Brilliant Cresyl Blue (BCB) or Safranin T (ST). The complex is easily extracted with chloroform. The absorbance of the chloroform extract is measured against either a blank or reference experiment. The latter is obtained by using a specific concentration of tolbutamide: 0.4 mg/mL in tolbutamide-BCB or 0.024 mg/mL in tolbutamide-ST. The ST complex method is more sensitive compared with the other methods. When the t-test is applied, the results of the proposed methods are more accurate than those of the traditional ultraviolet spectrophotometric method.
本文描述了两种分光光度法，即格伦正交函数法和碱性染料法，用于测定片剂中的甲苯磺丁脲，且不受片剂辅料的干扰。在格伦法中，在250 - 270nm附近以4nm间隔测量甲苯磺丁脲在95%乙醇中的吸光度，并计算p2系数。该系数在0.1 - 0.4mg/mL范围内与浓度呈线性关系。甲苯磺丁脲与碱性染料灿烂甲酚蓝（BCB）或番红T（ST）形成1:1的络合物。该络合物易被氯仿萃取。氯仿萃取液的吸光度相对于空白或参比实验进行测量。后者通过使用特定浓度的甲苯磺丁脲获得：在甲苯磺丁脲 - BCB中为0.4mg/mL，在甲苯磺丁脲 - ST中为0.024mg/mL。与其他方法相比，ST络合物法更灵敏。应用t检验时，所提出方法的结果比传统紫外分光光度法更准确。
