基于UHPLC-Q-TOF-MS/MS和LTQ-MSn联用技术快速鉴定绞股蓝皂苷类化学成分

目的 建立超高液相色谱-飞行时间高分辨质谱(UHPLC-Q-TOF MS/MS)和超高液相线性离子阱质谱(LTQ-MSⁿ)联用技术对绞股蓝中皂苷类成分快速鉴定的方法。方法 采用Thermo Syncronis C₁₈(2.1 mm×100 mm,1.7 μm)色谱柱,以纯水-乙腈为流动相梯度洗脱,质谱采用电喷雾(ESI)离子源,在负离子模式下采集数据对绞股蓝皂苷类进行成分鉴定。结果 初步鉴定了81种绞股蓝皂苷,其中包括58种已知皂苷和23种可能的未知皂苷结构。结论 UHPLC-Q-TOF-MS/MS可以提供化合物的准确相对分子质量及二级碎片信息,LTQ-MSⁿ可以提供化合物多级质谱信息,该联用技术可以简单、快速鉴定绞股蓝皂苷类成分,并为其质量控制、药效物质基础研究及进一步临床应用提供理论依据和科学研究思路。

Rapid Identification of Chemical Constituents of Gynostemma pentaphyllum Based on UHPLC-Q-TOF-MS/MS and LTQ-MSn

OBJECTIVE To establish a rapid identification method for saponins in Gynostemma pentaphyllum by ultra-high liquid chromatography-time-of-flight high-resolution mass spectrometry (UHPLC-Q-TOF MS/MS) and LTQ XL Linear Ion Trap Mass Spectrometer (LTQ-MSⁿ). METHODS A Thermo Syncronis C₁₈ (2.1 mm×100 mm, 1.7 μm) column was used. Water-acetonitrile was used as mobile phase for gradient elution. The mass spectrum was collected by electrospray ionization ion (ESI) source in negative ion mode. Accurate molecular, isotope distribution, multi-stage mass spectrometry and characteristic fragment ions were identified for the composition of Gynostemma saponins in combination with comparison with standard reference and literature. RESULTS A total of 81 Gynostemma saponins were identified, including 58 known components and 23 unknown components. CONCLUSION UHPLC-Q-TOF-MS/MS can provide accurate relative molecular mass and MS/MS information of compounds. LTQ-MSⁿ can provide MSⁿ information of compounds. This combination technique can easily and quickly identify Gynostemma saponins and provides an efficient data processing strategy to rapidly profile the chemical constituents of complicated herbal extracts.