在碱性和加热的条件下，头孢哌酮钠会降解为降解产物Ⅰ（R'SH）与降解产物Ⅱ（R″SH）两种巯基化合物。在pH为4.4时，R'SH可使Cu（Ⅱ）还原为Cu（Ⅰ），生成的Cu（Ⅰ）进一步与R″SH生成白色溶胶，导致体系产生共振散射效应，基于此建立了共振散射光谱法测定头孢哌酮含量的方法。优化试验条件如下：①氢氧化钠溶液浓度为0.20 mol·L^-1；②头孢哌酮钠的降解时间为40 min；③pH 4.4乙酸-乙酸钠缓冲溶液的用量为1.00 mL；④5.00 mmol·L^-1 Cu（Ⅱ）溶液用量为0.50 mL；⑤反应时间为2 min。头孢哌酮钠的质量浓度与反应体系共振散射强度变化量（ΔI_RSS）在0.02~2.40 mg·L^-1内呈线性关系，检出限（3s/k）为0.006 2 mg·L^-1。方法直接用于针剂中头孢哌酮钠含量的测定，加标回收率为97.5%~103%，测定值的相对标准偏差（n=5）为2.0%~2.6%。

Under the conditions of alkaline and heating, cefoperazone sodium could be degraded to two sulfhydryl compounds (R'SH and R″SH). At pH 4.4, Cu(Ⅱ) was reduced to Cu(Ⅰ) by R'SH and then generated leucosol with R″SH, which leaded to the resonance scattering signal (RSS) increase drastically. Based on this fact, a method of resonance scattering spectroscopy for determination of cefoperazone sodium was proposed. The optimized conditions found were as follows:1 concentration of sodium hydroxide solution:0.20 mol·L^-1; 2 degradation time of cefoperazone sodium:40 min; 3 amount of HOAc-NaOAc buffer solution at pH 4.4:1.00 mL; 4 amount of 5.00 mmol·L^-1 Cu(Ⅱ):0.50 mL; 5 time of reaction:2 min. Linear relationship was obtained between enhanced RSS intensity (ΔI_RSS) and concentration of cefoperazone sodium in the range of 0.02 to 2.40 mg·L^-1, with detection limit (3s/k) of 0.006 2 mg·L^-1. The proposed method was applied to the determination of cefoperazone sodium in injection, giving results of recovery in the range of 97.5% to 103%. Values of RSDs (n=5) found were in the range of 2.0% to 2.6%.