HPLC/DAD/MS法测定氯雷他定及其微量杂质

HPLC/DAD/MS determination of loratadine and its impurities

目的:建立高效液相色谱/二极管阵列检测器/质谱法(HPLC/DAD/MS)法测定氯雷他定及其2种合成过程中微量杂质地洛他定和N-甲基地洛他定,并对另一未知杂质结构进行鉴定。方法:采用RP-HPLC法,色谱柱:Alltima C18柱(150mm×4.6mm,5μm);流动相:乙腈-2%醋酸水溶液梯度洗脱,梯度条件如下:0min,10∶90;5min,10∶90;5.10min,30∶70;15.00min,30∶70;15.10min,50∶50;40.00min,50∶50;流速:1.0mL.min-1;柱温:35℃;进样量:10μL;检测波长:276nm;离子源:ESI,扫描模式:正离子扫描。未知杂质的分离制备采用RP-HPLC法,色谱柱:AlltimaC18半制备柱(250mm×10mm,10μm);流动相:乙腈-2%冰醋酸水溶液70∶30等度洗脱,流速3.8mL.min-1;检测波长296nm。采用600M核磁共振仪对未知杂质X进行1H-NMR的测定。结果:氯雷他定及其2种杂质分离良好。氯雷他定、地洛他定、N-甲基地洛他定分别在0.0102～10.2μg、0.00508～5.08μg、0.0053～5.32μg范围内线性关系良好(r=0.9996～0.9999);最低检测限分别为0.31,0.15,0.16ng;定量限分别为1.02,0.51,0.53ng。推测了该未知杂质X的化学结构为8-氯-11(1-羧酸乙酯基-4-哌啶基)-11H-苯并[5,6]芳庚并[1,2-b]吡啶,为氯雷他定的异构体。结论:该方法简便准确,可靠,重现性好,方法可行,可应用于原料药和制剂的质量研究和质量控制。

Objective：To establish a method of high performance liquid chromatography-diode array detection-mass spectrometry（HPLC/DAD/MS）to determine loratadine and its impurities which produced during the synthesis progress and identify the structure of an unknown impurity.Methods：Two HPLC methods were established.One method was achieved on a C18 column（150 mm×4.6 mm,5 μm）utilizing a mobile phase of acetonitrile-2% acetic acid solution（0 min,10∶90;5 min,10∶90;5.10 min,30∶70;15.00 min,30∶70;15.10 min,50∶50;40.00 min,50∶50）at a flow rate of 1.0 mL·min^-1 with a diode array detector set at 276 nm.The other method was achieved on a C18 semipreparative column（250 mm×10 mm,10 μm）utilizing a mobile phase of acetonitrile-2% acetic acid solution（70∶30）at a flow rate of 3.8 mL·min-1 with a diode array detector set at 296 nm for the unknown impurity separation and preparation.The chemical structure of the unknown impurity was elucidated by NMR spectra of ^1H-NMR.Results：Loratadine and its impurities could be separated with a good resolution.Loratadine,desloratadine and N-methyldesloratadine were liner over the range of 0.0102-10.2 μg,0.00508-5.08 μg,0.00532-5.32 μg（r=0.9996-0.9999）;The values of limit of detection were 0.31,0.15,0.16 ng,and values of limit of quantitation were 1.02,0.51,0.53 ng,respectively.The chemical structure of unknown impurity X had been identified as 8-chloro-11（1-ethoxycarbony-4-piperidinyl）-11H-benzo[5,6]cyclohepta[1,2-b] pyridine,which is one of isomers of loratadine.Conclusion：The method appeared to be simple,accurate,reliable,and reproducible,and can be applied to quality research and quality control of loratadine and its preparations.