Identification and characterization of forced degradation products and stability-indicating assay for notoginsenosidefc by using UHPLC-Q-TOF-MS and UHPLC-MS/MS: Insights into stability profile and degradation pathways.

Notoginsenoside Fc, a protopanaxadiol-type saponin, shows multi-pharmacological activities. Chemical stability evaluation plays a crucial role in drug development. In this study, the forced degradation behavior of Notoginsenoside Fc was investigated under hydrolytic and oxidative conditions. A specific ultra high performance liquid chromatography with quadrupole time-of-flight mass spectrometry was developed for the separation, identification, and characterization of the degradation products of Notoginsenoside Fc. Fifty potential degradation products were formed via deglycosylation, dehydration, hydration, isomerization, side-chain cleaving, oxidation, and superoxidation. Notoginsenoside Fc was subjected to different pH solutions, temperatures, and time periods to assess its stability. A sensitive ultra high performance liquid chromatography-tandem mass spectrometry was developed for the quantification of Notoginsenoside Fc, notoginsenoside ST-4, notoginsenoside Ft1, and relative quantification of notoginsenoside Ft2, 20(R)-notoginsenoside Ft2, notoginsenoside SFt3, and notoginsenoside SFt4. The assay was linear over the concentration range (R2  > 0.997) with the lowest limit of quantification of 0.02 μg/mL for Notoginsenoside Fc, Notoginsenoside ST-4, and Notoginsenoside Ft1. The intra-day precision, inter-day precision, and accuracy of the three analytes were within accepted levels. The degradation kinetics of Notoginsenoside Fc in pH 1 and 3 solutions fits to first- and second-order kinetics, respectively. The degradation of Notoginsenoside Fc is pH-, temperature-, and time-dependent.