Trends using biological target-based assays for drug detection in complex sample matrices

Recent applications of phosphodiesterase (PDE5) inhibition assays for detecting adulterated sexual enhancement products

“…The unpredictability and diversity of adulterants pose detection challenges by popular screening methods, especially mass spectrometry and immunoassays 7 . Targeted mass spectrometry requires prior knowledge of chemical structure and immunoassays do not have adequate selectivity to detect all the ED drugs/analogs, especially those that that are structurally unrelated to sildenafil, tadalafil, and vardenafil.…”

“…As analytical methods, PDE5 inhibition assays offer several unique advantages and serve as valuable, complementary tools for identifying products adulterated with ED drugs/analogs. The primary advantage of PDE5 inhibition assays is their ability to detect a range of structurally dissimilar ED drugs/analogs, including those that may be novel and have unpredictable chemical structures 7,8 . PDE5 inhibition assays are relatively inexpensive, rapid, and high throughput, making them potential candidates for routine consumer product screening.…”

“…The unpredictability and diversity of adulterants pose detection challenges by popular screening methods, especially mass spectrometry and immunoassays. 7 Targeted mass spectrometry requires prior knowledge of chemical structure and immunoassays do not have adequate selectivity to detect all the ED drugs/analogs, especially those that that are structurally unrelated to sildenafil, tadalafil, and vardenafil. Although untargeted methods (e.g., nuclear magnetic resonance and high-resolution mass spectrometry) can identify novel adulterants, these methods are relatively sophisticated and expensive, which may pose challenges for certain stakeholders.…”

“…Although untargeted methods (e.g., nuclear magnetic resonance and high-resolution mass spectrometry) can identify novel adulterants, these methods are relatively sophisticated and expensive, which may pose challenges for certain stakeholders. 7,8 Despite the unpredictable and diverse structures of the adulterants, they all specifically inhibit phosphodiesterase-5 (PDE5) activity, the pharmacological mechanism responsible for sexual enhancement (ED drugs/analogs are collectively known as "PDE5 inhibitors" for this reason). Traditionally, assays that measure inhibition of PDE5 activity have been mainly used in drug discovery, pharmacology, and toxicology research settings.…”

“…The primary advantage of PDE5 inhibition assays is their ability to detect a range of structurally dissimilar ED drugs/analogs, including those that may be novel and have unpredictable chemical structures. 7,8 PDE5 inhibition assays are relatively inexpensive, rapid, and high throughput, making them potential candidates for routine consumer product screening.…”