LC-MS/MS法测定脑透析液中人参皂苷Rg1浓度及对其体内和体外探针回收率的考察

Determination of ginsenoside Rg1 in intracerebral dialysate by LC-MS / MS and comparison of in vivo and in vitro recovery of microdialysis probe

目的建立高效液相色谱串联质谱(LC-MS/MS)方法,用于测定脑透析液中人参皂苷Rg1的浓度,并基于该方法考察Rg1在体外及大鼠海马、脑室的体内探针回收率,为Rg1在大鼠脑内的药代动力学研究奠定基础。方法高效液相色谱采用ACQUITY UPLC BEH C18色谱柱(2.1 mm×50 mm,1.7μm),以甲醇-水为流动相,进行梯度洗脱,流速为0.4 m L·min^(-1)。考察本方法的特异性、线性范围、精密度、准确度以及稳定性。分别采用将探针置于不同浓度标准溶液以及将探针植入对应脑区后通入不同浓度灌流液的方法,考察微透析探针对人参皂苷Rg1的体外以及体内回收率,并进一步比较两者间的差异。结果人参皂苷Rg1的保留时间为1.91 min,线性范围为0.1~50μg·L^(-1),日内、日间精密度(RSD)均小于15%。微透析探针对人参皂苷Rg1的体外回收率为(4.05±0.28)%,体内回收率为(26.96±4.45)%,且在9 h内稳定。结论 LC-MS/MS法准确、灵敏、重现性好,可用于大鼠脑微透析样品中人参皂苷Rg1的浓度测定。探针对Rg1的体外回收率可能受温度等多因素影响而低于体内回收率,因此体内回收率更接近体内透析环境和过程,是校正透析液浓度的可靠方法。

Aim To establish a LC-MS/MS method to measure the concentration of ginsenoside Rg1 in intrac-erebral dialysate and compare the probe recovery in vitro and in vivo. Methods The assay was conducted with a ACQUITY UPLC BEH C18(2. 1 mm × 50 mm, 1. 7 μm) . The mobile phase consisted of methanol and ultrapure water and it was detected by gradient elution. The flow rate was 0. 4 mL·min-1 . Specificity, linear range, precision and accuracy, stability were evaluated to investigate the reliability of the method. The recov-ery of ginsenoside Rg1 in probe in vitro and in vivo was compared. Results The retention time of ginsenoside Rg1 was 1. 91 min, the linear range was 0. 1 ~50 μg · L-1 , intra-day and inter-day precisions were less than 15%. The recovery of ginsenoside Rg1 was (4. 05 ± 0. 28)% in vitro and(26. 96 ± 4. 45)% in vi-vo. Conclusion The LC-MS/MS method is accurate, sensitive, and reproducible for quantitative determina-tion of ginsenoside Rg1 in microdialysate. The probe recovery of ginsenoside Rg1 in vivo is higher than in vitro, and both are stable in different concentrations.