注射用磷霉素钠中磷霉素钠二醇物含量测定方法的研究

目的:建立液相色谱串联质谱法和高效液相色谱-示差折光法测定注射用磷霉素钠中的磷霉素钠二醇物含量,并与现行中国药典方法比较,提高对药品的质量控制。方法:液相色谱串联质谱法采用Promosil CN(250 mm×4.6 mm,5μm)色谱柱,流动相为5 mmol.L-1醋酸铵-甲醇(82∶18),采用(-)ESI电离源,多反应监测(MRM)扫描方式,用于定量分析的离子分别为m/z 154.9→80.9(磷霉素二醇物)和m/z 120.9→77.1(内标苯甲酸)。高效液相色谱-示差折光法采用Agilent Zorb-ax NH2(250 mm×4.6 mm,5μm)色谱柱,流动相为10.89 g.L-1磷酸二氢钾溶液,流速为1.0 mL.min-1;柱温36℃;检测器温度为35℃。结果:采用液相色谱串联质谱法,二醇物在22.46～359.4 ng.mL-1范围内线性关系良好,定量限为4.492 ng.mL-1,每一样品的分析时间为5 min。采用高效液相色谱-示差折光法,二醇物在0.104～5.205 mg.mL-1浓度范围内线性关系良好,精密度为0.7%,重复性良好。结论:本研究2种方法专属性高、简便、可靠,可用于注射用磷霉素钠的质量研究和质量控制。

Study on the determination of fosfomycin sodium diol substance in fosfomycin sodium for injection

Objectives:To establish LC-MS/MS and HPLC-RID methods to determine fosfomycin sodium diol substance in fosfomycin sodium for injection,and compare with the method in Chinese Pharmacopoeia to improve the quality control of fosfomycin sodium.Methods:LC-MS/MS method was achieved on Promosil CN column(250 mm×4.6 mm,5 μm)with mobile phase consisting of 5 mmol·L-1 ammonium acetate solution-methanol(82∶ 18).The analytes were detected in the negative ion mode.Multiple reaction monitoring using the precursor to product ion combinations of m/z 154.9→80.9 and m/z 120.9→77.1 was performed to quantify fosfomycin diol substance and the internal standard benzoic acid,respectively.HPLC-RID method was achieved on Agilent Zorbax NH2 column(250 mm×4.6 mm,5 μm)utilizing a mobile phase of 10.89 g·L-1 potassium dihydrogen phosphate solution at the flow rate of 1.0 mL·min-1.The column temperature was 36 ℃ and the temperature of RID detector was set at 35 ℃.Results:The LC-MS/MS method:The standard curve was linear in the concentration range of 22.46-359.4 ng·mL-1.The lower limit of quantification was 4.492 ng·mL-1,each sample was chromatographed within 5 min.The HPLC-RID method:The standard curve was linear in the concentration range of 0.104-5.205 mg·mL-1,the method precision was 0.7%.Conclusions:The two methods are specific,simple and reliable,and can be applied to quality research and control of fosfomycin sodium for injection.