邻菲啰啉- Fe（Ⅱ）分光光度法测定头孢唑啉钠

摘要

A new spectrophotometric method has been established to determine cefazolin sodium using 1 ,10‐phenanthroline‐Fe ( Ⅱ ) .In the 0 .10 mol ・ L- 1 NaOH solution ,cefazolin sodium could be degraded to form the compound containing the sulfhydryl group at 100 ℃ water‐bath heating .It has been demonstrated that the Fe3 + could be reduced to form Fe2 + by cefazolin sodi‐um .By determining the absorbance of the orange complex after adding 1 ,10‐phenanthroline , the indirect determination of cefazolin sodium can be achieved .The concentration of cefazolin sodium has a good linear relationship in the range of 0 .02 - 40 mg ・L - 1 ,and the linear regres‐sion equation is A = 0 .043c(mg ・L - 1 ) - 0 .001 with a correlation coefficient of 0 .998 8 .What’s more ,the apparent molar absorption coefficient is 2 .05 × 104 L ・(mol ・cm) - 1 ,and the relative standard deviation is 1 .27% with the detection limit of 0 .065 mg ・L - 1 .This method has been applied to determine the cefazolin sodium powder injection in pharmaceuticals with satisfactory results .The recovery rate was in the range of 99 .17% - 101 .2% .%建立了用邻菲啰啉‐Fe（Ⅱ）分光光度法测定头孢唑啉钠的方法．头孢唑啉钠在0．10 mol ・L －1 NaOH 溶液中，100℃水浴加热降解为含巯基的化合物．巯基化合物把 Fe3＋还原为 Fe2＋．加入邻菲啰啉显色，通过测定生成的橘红色配位化合物的吸光度间接测定头孢唑啉钠的含量．头孢唑啉钠浓度在0．02～40 mg ・L －1范围内呈现良好线性关系，线性回归方程 A ＝0．043c（mg ・L －1）－0．001，相关系数 R ＝0．9988，表观摩尔吸光系数ε＝2．05×104 L ・（mol ・cm）－1，相对标准偏差 RSD ＝1．27％，检测限（3σ／k）0．065 mg ・L －1．在此基础上，测定了市售头孢唑啉钠粉针剂的含量，回收率在99．17％～101．2％之间，结果令人满意．