目的用高精度散射光度滴定法测定苯妥英钠。方法测定了苯妥英银凝胶的溶度积常数,研究了滴定的最优条件。结果滴定结果与对照试验测定结果无显著差异。结论用高精度散射光度滴定法测定苯妥英钠结果准确、重复性好、专属性强、线性范围宽。 Objective To determine phenytoin sodium by high-precision scattering photometric titration. The method was used to determine the solubility product constant of phenytoin silver gel and the optimum conditions of titration were studied. Results Titration results and the control test results no significant difference. Conclusion High-precision photometric photometric titration of phenytoin with accurate results, good repeatability, specificity, and wide linear range.