Method for the determination of Aconitum alkaloids in dietary supplements and raw materials by reversed-phase liquid chromatography with ultraviolet detection and confirmation by tandem mass spectrometry: single-laboratory validation.
A study of single-laboratory validation (SLV) of a reversed-phase liquid chromatography (RP-LC) method was conducted for the determination of diester-diterpene Aconitum alkaloids, viz., aconitine, mesaconitine, and hypaconitine, in a variety of dietary supplements, including single- and multiple-ingredient dry powder extracts, pills, capsules, and raw materials. The Aconitum alkaloids in the samples were extracted by diethyl ether in the presence of ammonia. After cleanup with solid-phase extraction to remove the matrix interferences, the alkaloids were determined by RP-LC with UV detection at 235 nm, and the results were confirmed by tandem mass spectrometry. The linear responses for aconitine, mesaconitine, and hypaconitine based on the present LC system ranged from 0.5 to 200 microg/mL. Relative standard deviations of 2.0 to 6.9% were obtained from duplicate analysis of 6 test materials of different matrixes for the 3 Aconitum alkaloids performed by 2 analysts on 5 different days. The recoveries determined for supplements and raw materials spiked with 3 Aconitum alkaloids at levels of 2.5-10 microg/g were in the range of 86-99%. In view of the attainment of satisfactory results for accuracy, precision, and recovery in the SLV study, it is recommended that the method validation process proceed to a collaborative study.
Tang
Wai-Tong
WT
Government Laboratory, 88 Chung Hau St, Homantin, Hong Kong SAR, China. wttang@govtlab.gov.hk
Wong
Sui-Kay
SK
Law
Tin-Yau
TY
Pang
Kwok-Chu
KC
Sin
Della
D
Tam
Yin-King
YK
D031841:Aconitum / Q000737:chemistry*; D000470:Alkaloids / Q000032:analysis*; D002138:Calibration; D002214:Capsules; D002851:Chromatography, High Pressure Liquid; D019587:Dietary Supplements / Q000032:analysis*; D007202:Indicators and Reagents; D013058:Mass Spectrometry; D010936:Plant Extracts / Q000032:analysis; D012015:Reference Standards; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet; D013607:Tablets
D000470:Alkaloids; D002214:Capsules; D007202:Indicators and Reagents; D010936:Plant Extracts; D013607:Tablets