Belal S, Elsayed M A, El-Waliely A, Abdine H
J Pharm Sci. 1979 Jun;68(6):750-3. doi: 10.1002/jps.2600680626.
Different approaches for the colorimetric determination of acetaminophen, based on its coupling with diazotized o-nitroaniline, are described. Copper(II) chelation with the coupled compound makes the method highly selective. Sensitivity is increased when the acetaminophen assay is carried out indirectly through the determination of the chelate's copper content. Optimum conditions for performing the different approaches are described. The stoichiometric balance for the reactants in the coupled compound and chelate is determined. The degree of dissociation and the instability constant are computed. The rectilinear relationship between the absorbance of the different products and the concentration of acetaminophen allows for its determination in different pharmaceutical formulations. Compared with the official method, the proposed methods give more accurate results.
本文描述了基于对乙酰氨基酚与重氮化邻硝基苯胺偶联反应的比色法测定的不同方法。与偶联化合物形成的铜（II）螯合物使该方法具有高度选择性。当通过测定螯合物中的铜含量间接进行对乙酰氨基酚测定时，灵敏度会提高。文中描述了执行不同方法的最佳条件。确定了偶联化合物和螯合物中反应物的化学计量平衡。计算了解离度和不稳定常数。不同产物的吸光度与对乙酰氨基酚浓度之间的线性关系使其能够在不同药物制剂中进行测定。与官方方法相比，所提出的方法给出了更准确的结果。
