超临界流体色谱法拆分阿托伐他汀钙及其对映异构体杂质

Chiral Separation of Atorvastatin Calcium and Its Enantiomeric Impurity by Supercritical Fluid Chromatography

目的建立一种超临界流体色谱方法拆分调血脂药阿托伐他汀钙与其对映异构体杂质,并对对映异构体杂质进行含量测定。方法采用ACQUITY UPC^2Trefoil CEL2色谱柱(3. 0 mm×150 mm,2. 5μm),以超临界二氧化碳/含0. 1%三氟乙酸的甲醇(78/22,V/V)为流动相,背压为13. 8 MPa,进样量为4μL,柱温为45℃,流速为1. 5 m L·min^(-1),于244 nm波长处分离阿托伐他汀钙及其对映异构体。结果阿托伐他汀钙与其对映体在5 min内均已出峰完全,分离度达4. 1,对映体在2. 5～50μg·m L^(-1)内线性关系良好,相关系数为0. 999 9(n=6)。对映体的检测限与定量限分别为1. 0μg·m L^(-1)(S/N=3)和2. 5μg·m L^(-1)(S/N=10);阿托伐他汀钙原料药中对映异构体的平均加样回收率为100. 40%。结论利用超临界流体色谱分离阿托伐他汀钙手性杂质与使用普通液相色谱相比可极大缩短分离时间,减少有机溶剂的使用量,重现性好,可有效用于阿托伐他汀钙的质量控制。

OBJECTIVE To develop a supercritical fluid chromatography method for the separation of atorvastatin calcium and its enantiomer, meanwhile assaying the enantiomer. METHODS Atorvastatin calcium and its enantiomer were separated on a ACQUITY UPC2 Trefoil CEL2 column（3.0 mm×150 mm, 2. 5μm） maintained at 45℃ with the mobile phase containing a mixture of CO2 and methanol with 0. 1% TFA（78： 22, V/V） at 1.5 mL·min^-1 , and the detection wavelength was set at 244 nm. The back pressure was set at 13.8 MPa. RESULTS The enantiomer and atorvastatin calcium were separated successfully in 5 min with a resolution factor of 4. 1. Good linear relationship was established between the peak response and the concentration in the range of 2. 5 - 50 μg · mL^ - 1 for enantiomer（r^2 =0. 999 9, n =6）, the quantitative limit（S/N = 10） was 2. 5 μg · mL^-1, and the detection limit（S/N =3） was 1.0 μg · mL ^-1. The spiked recovery of the enantiomer was 100.40% （ n = 9 ）. CONCLUSION The proposed method shows high accuracy, repeatability and stability. It can be employed for the quality control and stability research of the enantiomer of atorvastatin calcium.