不同血浆样品制备方法对芍药苷血液药物浓度测定的影响

目的比较乙腈法、高氯酸法和磷酸二氢钠酸化法三种不同的血浆样品处理方法对芍药苷血液药物浓度测定的影响,优选最佳的血浆样品处理方法。方法高效液相色谱法测定血浆样品中不同浓度的芍药苷,比较三种方法对样品中芍药苷的回收率、检测的灵敏度以及实验结果可重复性等方面的影响。结果用乙腈和高氯酸处理芍药苷浓度>50μg/ml的血浆样品时,均能得到较高的回收率;但对于芍药苷浓度<50μg/ml的血浆样品,仅高氯酸处理的样品才能得到较高的回收率;并且高氯酸处理血浆能检测的最低芍药苷血液药物浓度为0.5μg/ml,具有较好的灵敏度。结论对于检测芍药苷的血液药物浓度,用高氯酸处理血浆样品最为适合。

Impacts of varied preparation approaches on plasma paeoniflorin assay

Objective To compare the impacts of varied preparation approaches on plasma Paeoniflorin assay, in search of the optimum of choice for analysis. Methods A simple and specific high performance liquid chromatographic （HPLC） method with UV detection using pentoxifylline as the internal standard was developed and validated to determine the concentration of paeoniflorin in rat plasma. The plasma samples, which contained different concentration of Paeoniflorin （0.5, 1, 10, 50 μg/mL） and 4.5 μg/ml of pentoxifylline, were treated with aeetonitrile or 4.5% perchloric acid （pH 0.72） or ethyl acetate after acidification with 0.05 mol/L NaH2PO4 solution （pH 5.0）, respectively. Chromatographic separation was achieved on an Agilent ODS C18 column （250 mm×4.6 mm, 5 μm） using a mobile phase consisting of water： methanol （86：14, V/V） at a flow rate of 1.0 ml/min. The UV detection was performed at a wavelength of 230 nm. The linear calibration curves were obtained in the concentration range of 0.002-1 μg in rat plasma with the lower limit of quantification of 0.05 μg/mL. The extraction recoveries, sensitivity and reproducibility of paeoniflorin were evaluated among samples. Results Below a plasma paeoniflorin of 50 μg/mL, the extraction recoveries of paeoniflorin were higher in samples treated with 4.5% perchloric acid those with other agents. However, the best recovery of paeoniflorin was achieved in acetonitrile-treated sample when the plasma concentration of paeoniflorin was above 50 μg/mL. Moreover, the minimal detectable level of Paeoniflorin was 0.5 μg/mL with perchloric acid treated samples, which demonstrated better sensitivity. Conclusion Perchloric acid treatment appeared optimal for determination of the plasma paeoniflorin.