Simultaneous screening of 21 potential adulterants in dietary supplements for the treatment of prostate diseases using ultra‐performance liquid chromatography and liquid chromatography‐electrospray ionization‐tandem mass spectrometry

Reports of the number of adulteration cases using illegal therapeutic substances in dietary supplements have increased. In recent years, various dietary supplements are being distributed that exaggerate the efficacy of treatment for prostate‐related diseases. To develop the preemptive monitoring method, we selected 21 prostate‐related therapeutic substances and optimized the simultaneous ultra‐performance liquid chromatography and liquid chromatography‐electrospray ionization‐tandem mass spectrometry and pretreatment procedures for various types of matrices including solid, liquid, and soft capsule samples. The methods were validated by determining the specificity, linearity, limit of detection, limit of quantification, method detection limit, method quantitation limit, precision, accuracy, recovery, stability, and matrix effect. The simultaneous methods were validated according to the international guidelines. In addition, using the validated methods, 81 real samples, which were searched and purchased by focusing on promotional phrases, such as prostate and prostatic hyperplasia, were successfully screened. As a result, sildenafil and tadalafil were detected in one seized capsule sample (5.15 and 14.6 mg/g, respectively). Synthetically, our approach could be useful for the determination of illegal therapeutic substances potentially adulterated in various types of dietary supplements.