场放大进样-胶束扫集毛细管电脉法测定痕量泼尼松

Determination of prednisone by micellar electrokinetic chromatography using field-amplified sample stacking and sweeping micellar electrokinetic chromatographic technique

建立了胶束毛细管电动色谱在线富集技术测定药品中痕量的泼尼松的方法。在胶束扫集的基础上联用场放大进样,使泼尼松的富集倍数提高了136倍;检出限由原来的2.7mg/L降至20μg/L。胶束扫集毛细管电泳缓冲体系为120mmol/LSDS、10mmol/LNaH2PO4(pH2.5)10%乙腈(V/V)。分离电压-20kV,进样电压-20kV,进样时间70s,进水时间180s,检测波长250nm。同时讨论了SDS浓度、样品基质pH、进样电压、进水时间和进样时间对分离效果的影响。实验结果显示:在优化实验条件下,样品的检测仅需8min,泼尼松在0.05～10mg/L的范围内线性关系良好(r=0.998)。回收率在89.4%～106%之间,相对标准偏差在2.1%～2.6%之间,可用于各种中药制剂中泼尼松的含量测定。

Two online preconcentration techniques including field-amplified sample stacking and sweeping micellar electrokinetic chromatographic techniques (FASS-sweep MEKC) were used in determination of prednisone. The sensitivity was improved about 136 times. The LODs decreased from 2.7 mg/L to 20 μg/L. The buffer medium contains 120 mmol/L SDS,10 mmol/L NaH2PO4 (pH 2.5),10% (V/V) acetonitrile. Separation voltage was-20 kV,sample injection voltage-20 kV,sample injection time was 70 s,water injection time was 180 s,d...