Simultaneous Determination of Resveratrol and Polydatin in Polygonum Cuspidatum by Quantitative Nuclear Magnetic Resonance Spectroscopy / 分析化学

ABSTRACT

A quantitative nuclear magnetic resonance spectroscopic ( qNMR) method was established for the simultaneous determination of resveratrol and polydatin in Polygonum Cuspidatum traditional Chinese herb cuts and granule. The 2_step ultrasonic extraction method using 80% alcohol and acetone was used for fully extracting these two components in samples before qNMR determination. The qNMR experimental conditions were investigated and deuterated dimethyl sulphoxide_deuterium oxide (10∶1, V/V) was selected as solvent, the pulse delay time was 5 s, the scan number was 32, 2,3,5_triiodobenzoate was used as internal standard which was calibrated with primary standard substance of potassium hydrogen phthalate. The 1 H_NMR peaks atδ6. 388-6. 391 ( d, 2H) of resveratrol and δ 6. 322-6. 330 ( t, 1H) of polydatin were chosen as the quantitative peaks. Method validation was performed in terms of precision ( RSD0. 999), limit of detection (0. 23 g/L for resveratrol and 0. 24 g/L for polydatin) and limit of quantitation ( resveratrol 0. 69 g/L, polydatin 1. 57 g/L), recovery ( resveratrol 97. 7% -103 . 5%, RSD=2 . 4%, polydatin 94 . 5%-99 . 2%, RSD=1 . 6%, including the sample extraction and preparaton process) . The results showed the reliability of qNMR for traditional Chinese medicine assay. The resveratrol and polydatin in Polygonum Cuspidatum real cuts and granule samples were experimental determined as 3. 57-5. 69 mg/g and 12. 73-24. 07 mg/g, respectively.