Website: https://vjfc.nifc.gov.vn/
Website: https://vjfc.nifc.gov.vn/
Phosphodiesterase type 5 inhibitors (PDE-5i) are the common oral medications prescribed for the treatment of erectile dysfunction (ED). In recent years, health supplements have gained popularity as alternative options to prescription PDE-5i. However, concerns have emerged regarding the adulteration of these products with undeclared synthetic PDE-5i or their analogues, posing significant health risks. In this study, a rapid, simple, and efficient analytical method for the determination of PDE-5i was developed and validated using a liquid chromatography–tandem mass spectrometry system (LC-MS/MS) for the rapid detection of these compounds in health supplement products collected in Hanoi. The method demonstrated excellent linearity (R² ≥ 0.999). The limits of detection (LOD) and quantification (LOQ) were 1.5 µg/kg and 5.0 µg/kg for sildenafil, tadalafil, and vardenafil, and 15 µg/kg and 50 µg/kg for the remaining PDE-5i. Recoveries ranged from 80.9% to 113% with relative standard deviations (%RSD) below 15%. The validated procedure was applied to 24 real-world samples, and 13 of them were found to contain PDE-5i. Further comprehensive investigations involving larger sample sizes and additional PDE-5i compounds are necessary to better assess adulteration practices and potential health risks.
Phosphodiesterase type 5 inhibitors, Adulterants, Health supplements, LC-MS/MS.
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