DESI-MSI技术在经典名方芍药甘草汤质量控制中应用研究

Study on application of DESI-MSI in quality control of classical famous prescription Shaoyao Gancao Decoction

目的使用超高效液相色谱-二极管阵列检测器检测法(UHPLC-DAD)和解吸电喷雾电离-离子化质谱成像技术(desorption electrospray ionization-mass spectrometry imaging,DESI-MSI)对15批芍药甘草汤(Shaoyao-Gancao-Decoction,SGD)物质基准和对应实物进行分析,考察DESI-MSI在经典名方SGD质量控制中的优势。方法以SGD为研究模型,采用传统UHPLC-DAD法建立物质基准指纹图谱,并对SGD指标成分(芍药苷、甘草苷、甘草酸)含量、出膏率进行考察。同时,以芍药甘草汤对应实物冻干粉为研究载体,将其复溶后点样于定性滤纸,并固定于载玻片制成样品,以甲醇-甲酸(1000∶1)为喷雾溶剂,体积流量3μL/min;扫描范围m/z 100~1200;空间分辨率300μm;喷雾气(N2)压力0.5 MPa;离子源温度120℃,采用正负离子全扫描样本。结果DESI-MSI法能检测到SGD指标成分芍药苷、甘草苷、甘草酸以及共有峰成分芍药内酯苷等。同时,DESI-MSI法还能检测到来自甘草、白芍的甘草皂苷G2、甘草皂苷J2、没食子酸、柠檬酸、对羟基苯甲酸等11种成分,并对其相对含量进行直观呈现,定性分析能力远强于UHPLC-DAD法。结论基于DESI-MSI技术无需进行复杂的样品前处理,可以在无对照品情况下进行复杂样品的定性、相对含量分析,灵敏度高,分析能力强,可以作为经典名方物质基准、对应实物及配方颗粒样品的质控研究方法。

Objective Using ultra-high performance liquid chromatography with diode array detection(UHPLC-DAD) and desorption electrospray ionization-mass spectrometry imaging(DESI-MSI) to analyze 15 batches of Shaoyao Gancao Decoction(SGD) substance benchmark and lyophilized powder in order to investigate the advantages of DESI-MSI in quality control of famous classical formulas. Methods Taking SGD as the research model, fingerprints of the substance benchmark were established by UHPLC-DAD, and the content of index components(paeoniflorin, liquiritin, glycyrrhizic acid) and the yield of dry extract were also investigated. Meanwhile, as the research carrier, the lyophilized powder corresponding to SGD was dissolved in methanol and dotted on qualitative filter paper with quantitative capillary, and fixed it on the slide to make samples. The samples were analyzed on a DESI-MSI system in positive and negative ion mode with methanol-formic acid(1 000∶1, flow rate of 3 μL/min) as spray solvent, N2 as spray gas(pressure of 0.5 MPa). The scanning range was m/z 100—1 200, the spatial resolution was 300 μm, the ion source temperature was 120 ℃. Results DESI-MSI can detect not only the index components of paeoniflorin, liquiritin, glycyrrhizic acid, but also the common peaks of albiflorin. At the same time, DESI-MSI could detect 11 other components from Glycyrrhizae Radix et Rhizoma and Paeoniae Radix Alba, such as licoricesaponin G2, licoricesaponin J2, gallic acid, citric acid, p-hydroxybenzoic acid, and present their relative content visually. The qualitative analysis ability of DESI-MSI was much better than UHPLC-DAD. Conclusion DESI-MSI can be used as the quality control method for substance benchmark and lyophilized powder and dispensing granules of classical famous formulas with advantages of high sensitivity, strong analytical ability, no complex sample pretreatment, qualitative and relative content analysis of complex samples without reference substance.