Development of a Matrix Solid-Phase Dispersion Extraction Combined with UPLC/Q-TOF-MS for Determination of Phenolics and Terpenoids from the Euphorbia fischeriana

A method based on a simplified extraction by matrix solid phase dispersion (MSPD) followed by ultra-performance liquid chromatography coupled with the quadrupole time-of-flight tandem mass spectrometry (UPLC/Q-TOF-MS) determination is validated for analysis of two phenolics and three terpenoids in Euphorbia fischeriana. The optimized experimental parameters of MSPD including dispersing sorbent (silica gel), ratio of sample to dispersing sorbent (1:2), elution solvent (water–ethanol: 30–70) and volume of the elution solvent (10 mL) were examined and set down. The highest extraction yields of chromatogram information and the five compounds were obtained under the optimized conditions. A total of 25 constituents have been identified and five components have been quantified from Euphorbia fischeriana. A linear relationship (r2 ≥ 0.9964) between the concentrations and the peak areas of the mixed standard substances were revealed. The average recovery was between 92.4% and 103.2% with RSD values less than 3.45% (n = 5). The extraction yields of two phenolics and three terpenoids obtained by the MSPD were higher than those of traditional reflux and sonication extraction with reduced requirement on sample, solvent and time. In addition, the optimized method will be applied for analyzing terpenoids in other Chinese herbal medicine samples.


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Barker firstly introduced matrix solid phase dispersion (MSPD) technology in 1989 for the 76 extraction of drug residues from animal tissue [26]. Since then, the technique has induced considerable interests because of the unique properties of MSPD providing the simple, low-cost and 78 convenient benefits. As one of the most promising techniques, MSPD has been successfully applied 79 to solve many difficult analytical problems. Recnetly, MSPD has been applied more and more 80 frequently as a potential and effective alternative to conventional extraction methods in the 81 extraction of active ingredients from medicinal plants [27][28]. However, there is no report on MSPD 82 as a extraction method for the simultaneous extraction of active compounds mainly the terpenoids 83 from E. fischeriana. in the literature to our best knowledge.

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In this study, to achieve the maximum extraction yield, MSPD as alternative sample preparation 85 method followed by UPLC/Q-TOF-MS separation was applied to extract and determine the main 86 two phenolics and three terpenoids and other components in E. fischeriana. The effects of MSPD 87 extraction for terpenoids were evaluated and optimized by various operating parameters, including 88 dispersing sorbent, elution solvent and volume, the ratio of dispersing sorbent to sample. Then a 89 validation for HPLC method, including linearity, precision, accuracy and so on were evaluated.

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C18-bonded silica were tested in this step. The results of extraction yields of terpenoids from E.

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Fischeriana obtained with the four different dispersing sorbents were shown in Table 1. As can be 105 seen, when we used the silica gel, the extraction yields which is calculated by the ratio of extracted 106 compound to medicinal material of the two phenolics and three terpenoids were a little higher than 107 the extraction yields with the other three sorbents. Therefore, silica gel was the dispersing sorbent 108 selected for MSPD because of the best extraction yields for the two phenolics and three terpenoids 109 and the relatively low cost. with the increase of mass ratios of sample to silica gel less than 1:2. Further increasing the mass 118 ratio to 1:3 or 1:4 resulted in no significant increase even reduction of extraction yields of the two 119 phenolics and three terpenoids. Thus, the optimized mass ratio was selected at 1:2 in this work. 120 121

Optimization of UPLC conditions
To obtain desirable UPLC chromatograms, the procedure of sample separation was optimized in 141 selecting the factors of extraction method, separation solvent and so on. Acetonitrile-water 142 possessed better resolution and peak shape than methanol-water system. It was also found that 143 good signal intensity, resolution and peak shape were achieved when 0.1% (v/v) formic acid was 144 added to aqueous solution. To sum up, we determined the different kinds of compounds in 145 Euphorbia fischeriana with mobile phase consisted of A (acetonitrile) and B (0.1% v/v aqueous formic 146 acid). In order to screen and separate the components completely, a high-gradient slope was used.

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The UV detection wavelength was set at 210 nm, at which most components can be detected 148 sensitively.            filtered. This extraction was repeated once more. The combined filtrate was evaporated to dryness.

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The residue was then dissolved and diluted using methanol to 50 mL volumetric flask and filtered 276 through a 0.45 μm filter membrane before analysis.

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The method offers advantages of shorter analytical time, less reagents consumption, and 369 simplicity over existing systems as well as excellent selectivity and sensitivity were shown. This