建立了在线加压溶剂微提取-湍流色谱-高效液相色谱(online PLME-TFC-HPLC)法,并将其应用于管花肉苁蓉中松果菊苷、毛蕊花糖苷和异毛蕊花糖苷3种苯乙醇苷类成分含量的同时测定。微量样品粉末(0.5 mg)置于空预柱芯中并用正相硅胶填充,得到提取池后装入预柱套(Security Guard^TM)。将预柱套置于70℃柱温箱中,将一根长聚醚醚酮(PEEK)管线(1 000 mm×0.13 mm)连于预柱套末端,采用0.1%(v/v)甲酸水为提取溶剂,以2.5mL/min的速度流经PEEK管线,产生高压,实现管花肉苁蓉的在线加压溶剂微提取,通过TurboFlow cyclone色谱柱在线净化和富集。引入两个电子六通阀,将整个分析过程分为提取阶段和洗脱阶段,并在洗脱阶段将TurboFlow cyclone色谱柱中的分析物反冲至Capcell PAK C_(18)AQ分析柱上,以0.1%(v/v)甲酸水-乙腈为流动相进行梯度洗脱,以340 nm为检测波长同时定量分析松果菊苷、毛蕊花糖苷和异毛蕊花糖苷3种苯乙醇苷类成分。结果表明,3种苯乙醇苷类在1-200 mg/L范围内线性良好,相关系数r均大于0.999,定量限分别为0.50 mg/L(松果菊苷)、0.25 mg/L(毛蕊花糖苷)和0.38 mg/L(异毛蕊花糖苷),加标回收率为83.13%-114.00%,相对标准偏差为1.89%-13.34%。该方法简便、快速、可靠,不仅节约了药材和溶剂的使用量,而且极大地简化了前处理方法,省时省力,同时显著降低了化学成分在提取过程中降解的几率,适用于管花肉苁蓉中苯乙醇苷类化合物的含量测定。
An online pressurized liquid microextraction-turbulent flow chromatography-high performance liquid chromatography(online PLME-TFC-HPLC) platform was configured for simultaneous determination of three phenylethanoid glycosides in Cistanche tubulosa. Micro amount powder of crude material(0. 5 mg) was mixed with clean diatomaceous earth and packed into a vessel which then was put into a hollow guard column. To generate high temperature and high pressure,a long polyetheretherketone(PEEK)tube(1 000 mm × 0. 13 mm)was linked to the end of the hollow guard column that was warmed in the column oven(70 ℃). The water containing 0. 1%(v / v)formic acid acted as the extraction solvent and was delivered at2. 5 mL / min. Two electronic 6-port / 2-channel valves were responsible for dividing the whole program into extraction and elution phases. The analytes were purified and enriched in a TurboFlow cyclone column,and back-flushed onto a Capcell PAK C_(18) AQ column under a gradientelution program with 0. 1%(v / v)aqueous formic acid-acetonitrile at the elution phase. The ultraviolet wavelength was set at 340 nm to monitor phenylethanoid glycosides. The calibration curves for the three phenylethanoid glycosides revealed good linearities in the range of 1- 200 mg / L(r〉0.999). The limits of quantification(LOQs)were 0. 50 mg / L(echinacoside),0. 25 mg / L(acteoside)and 0. 38 mg / L(isoacteoside). The spiked recoveries were in the range of83. 13%-114. 00% with the relative standard deviations(RSDs)between 1. 89% and 13. 34%. All the results indicated that this method is facile,efficient,reliable,and advantageous at time,labor,solvent,and material savings. The method also reduces the degradation risks and is suitable for the determination of phenylethanoid glycosides in Cistanche tubulosa.