Analysis of phosphodiesterase type 5 inhibitors as possible adulterants of botanical-based dietary supplements: extensive survey of preparations available at the Czech market

Screening of Phosphodiesterase-5 Inhibitors and Their Analogs in Dietary Supplements by Liquid Chromatography–Hybrid Ion Trap–Time of Flight Mass Spectrometry

“…The retention times and mass errors of all analytes are listed in Table 1, and the extracted ion chromatograms are depicted in Figure 1. (6), piperidinohongdenafil (7), homosildenafil (8), dimethylsildenafil (9), udenafil (10), cyclopentinafil (11), thiosildenafil (12), hydroxythiohomosildenafil (13), thiohomosildenafil (14), dimethylthiosildenafil (15), oxohongdenafil (16), benzylsildenafil (17), hydroxychlorodenafil (18), chlorodenafil (19), nitrodenafil (20), nor-neosildenafil (21), dichlorodenafil (22), vardenafil (23), acetylvardenafil (24), hydroxyvardenafil (25), nor-neovardenafil (26), desulfovardenafil (27), pseudovardenafil (28), tadalafil (29), aminotadalafil (30), acetaminotadalafil (31), demethyltadalafil (32), chloropretadalafil (33), N-octyltadalafil (34), yohimbine (35), mirodenafil (36), thioquinapiperifil (37), xanthoanthrafil (38), and phenolphthalein (39). * indicated the analytes among multiple peaks in the EIC.…”

“…In this regard, various spectrometric and chromatographic methods have been adopted to analyze the illegally added drugs in complex matrices [ 3 , 4 , 5 , 9 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. High-performance liquid chromatography with diode array detection (HPLC–DAD) and liquid chromatography with mass spectrometry (LC–MS) have been previously used to detect PDE-5 inhibitors and their analogs [ 3 , 5 , 7 , 8 , 9 , 10 , 16 , 17 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. When the standards of PDE-5 inhibitors and their analogs are available, HPLC with a UV spectrometer is a simple method for quantitative analysis [ 11 ].…”

“…Further, QqQ MS can only be used for the quantitative analysis of known compounds and not for screening purposes. Therefore, other spectroscopic methods such as high-resolution mass spectrometry (HRMS) based on Fourier transform ion cyclotron resonance (FT-ICR) [ 31 ], time of flight (TOF) [ 24 , 25 , 28 , 29 , 33 ], orbitrap [ 8 , 12 , 26 , 27 ], and nuclear magnetic resonance spectrometry [ 4 , 6 , 7 , 9 , 30 , 34 , 35 , 36 , 37 , 38 ] must be applied to clarify the structure of the analytes. In particular, hybrid ion trap (IT)–HRMS, including IT–TOF and Orbitraps (LTQ–Orbitrap and Orbitrap Fusions), is one of the most effective tools for screening and identification of unknown compounds owing to its high-resolution and multistage tandem MS (MS n ) ability.…”

HPLC Determination of Sildenafil in Tablets

“…Many dietary supplements (advertised as "natural" or "herbal") are available on the market to help combat erectile dysfunction or improve sexual activity. Low control on such products makes it possible to insert medicines of unclear origin and quality, which in turn lead to health risks [5][6][7][8].…”

“…Various analytical techniques like spectrophotometry [9,11], Raman spectroscopy [11,12], thin layer chromatography [13], high performance liquid chromatography [14][15][16][17][18][19][20][21][22][23], high performance liquid chromatography-mass spectrometry [24][25][26][27] are reported for Sildenafil determination in pharmaceutical preparations [10, 12, 18-20, 22, 23, 25], biological samples [16,20,21,[24][25][26][27], dietary supplements [3,5,13], herbal products [15] and drinks [11].…”