RTI International, Research Triangle Park, North Carolina 27709-2194, USA.
J Anal Toxicol. 2011 Jul;35(6):341-8. doi: 10.1093/anatox/35.6.341.
A rapid and simple liquid chromatography tandem mass spectrometry method was developed and validated for the simultaneous determination of L-ephedrine, pseudoephedrine, and caffeine in male Fisher-344 rat plasma at nanogram-per-milliliter concentrations for use in support of toxicology studies. Only 25 μL of plasma is required, and extraction is performed using a simple, single-step protein precipitation. The method was validated over a range of 2.09 to 5460 ng/mL for L-ephedrine, 2.09 to 5050 ng/mL for pseudoephedrine and 2.03 to 5340 ng/mL for caffeine. A binary gradient elution at 0.3 mL/min was used with a Waters XBridge Phenyl (2.1 × 150 mm, 3.5 μm) column and a Waters XBridge Phenyl 2.1- × 10-mm guard column at ambient temperature. The mobile phase consisted of 10 mM ammonium acetate in water (pH 5.0) and methanol. Caffeine trimethyl-(13)C(3) was used as the internal standard. The method was evaluated for linearity, recovery, precision, accuracy, and stability, and it was successfully applied in toxicokinetic studies of ephedrine, administered alone, in combination with caffeine, and in the herbal source Ma Huang.
建立并验证了一种快速、简单的液相色谱-串联质谱法，用于同时测定纳克/毫升浓度的雄性 Fisher-344 大鼠血浆中的 L-麻黄碱、伪麻黄碱和咖啡因，以支持毒理学研究。仅需 25 μL 血浆，采用简单的一步蛋白沉淀进行提取。该方法在 L-麻黄碱 2.09 至 5460ng/mL、伪麻黄碱 2.09 至 5050ng/mL 和咖啡因 2.03 至 5340ng/mL 的范围内进行了验证。采用 Waters XBridge Phenyl（2.1×150mm，3.5μm）柱和 Waters XBridge Phenyl 2.1-×10mm 保护柱，在 0.3mL/min 的二元梯度洗脱条件下，以室温下 10mM 乙酸铵水溶液（pH5.0）和甲醇作为流动相。使用咖啡因三甲基-(13)C(3)作为内标。该方法经过线性、回收率、精密度、准确度和稳定性评估，并成功应用于麻黄碱、咖啡因联合给药以及草药麻黄的毒代动力学研究。
