Qualitative and quantitative analysis of 31 PDE-5 inhibitors in herbal products and dietary supplements by UPLC/Q-TOF-MS / 中国药学杂志

ABSTRACT

OBJECTIVE: To develop an applicable approach to rapidly analyze 31 PDE-5 inhibitors qualitatively and quantitatively and provide a strategy for detection and rapid identification of similar derivatives in herbal products and dietary supplements based on high-resolution quadrupole-time-of-flight mass spectrometry (Q-TOF-MS). METHODS: The analysis was performed on an Agilent ZORBAX RRHD Eclipse Plus C18 column with the mixture of 0.1% formic acid-acetonitrile-water as mobile phase, and the flow rate was 0.4 mL · min. Q-TOF-MS equipped with ESI ion source was performed in positive ionization mode. Qualitative analysis was based on the accurate mass, the elemental compositions and the product ions. Quantitative analysis was performed by using the peak area and concentration of each compound. RESULTS: The ESI-MS fragmentation behaviors of three common structural skeletons (sildenafil, vardenafil, and tadalafiland) were characterized and summarized. Good linearity was obtanined in the ranges of 1-200, 5-400 or 20-600 ng · mL-1 for the calibration curves of the 31 analytes(r≥0.9974). The LOQs were 0.07-37.82 pg, recoveries were 75.00%-124.56%, and RSDs were less than 7.56% (n=6). CONCLUSION: The established method is simple, accurate and reliable. It is suitable for determining PDE-5 inhibitors and rapid detection of similar derivatives in herbal products and dietary supplements.