Quantitative analysis of four major diterpenoids in Andrographis paniculata by 1H NMR and its application for quality control of commercial preparations.
A quantitative proton nuclear magnetic resonance technique (qHNMR) has been successfully introduced to quantify andrographolide, dehydroandrographolide, deoxyandrographolide and neoandrographolide in Andrographis paniculata, a commonly used important traditional Chinese medicine. Creative use of trifluoroacetic acid-d, which satisfactorily resolved the overlapping signals of these compounds in crowded regions of δ 4.5-5.6 ppm in (1)H NMR spectrum, made their quantification possible. Optimization of other experimental conditions, including internal standard, NMR pulse sequence, and NMR relaxation delay time, finally established the (1)H NMR based quantification approach, which was validated with satisfactory accuracy, precision, repeatability, and recovery. Except for deoxyandrographolide and neoandrographolide in two compound recipes, this method was successfully applied to quantify the four major components in fourteen raw herb materials and five commercial preparations, providing quantification results in good agreement with those determined by HPLC. The inherent advantages of qHNMR, such as its rapidity and simplicity, make itself a feasible alternative to HPLC for the quality control of A. paniculata raw material and herbal preparations.
State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing 210009, China.
Minghua
M
Yang
Junsong
J
Wang
Lingyi
L
Kong
D035685:Andrographis / Q000737:chemistry*; D002138:Calibration; D004224:Diterpenes / Q000032:analysis*; D005240:Feasibility Studies; D005960:Glucosides / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy / Q000592:standards; D028321:Plant Preparations / Q000032:analysis* / Q000592:standards; D011786:Quality Control; D012015:Reference Standards; D015203:Reproducibility of Results; D013764:Tetrahydronaphthalenes / Q000032:analysis; D014269:Trifluoroacetic Acid / Q000737:chemistry
D004224:Diterpenes; D005960:Glucosides; D028321:Plant Preparations; D013764:Tetrahydronaphthalenes; C030419:andrographolide; D014269:Trifluoroacetic Acid; C478098:dehydroandrographolide; C082497:neoandrographolide