Profiling counterfeit Cialis, Viagra and analogs by UPLC-MS

In this work, the chemical profile of 43 commercial samples of tablets for male erectile dysfunction (Viagra (R), Cialis (R), Lazar (R), Libiden (R), Maxfil (R), Plenovit (R), Potent 75 (R), Rigix (R), Vimax (R), Pramil (R) 75 and Pramil (R)) and 65 counterfeit samples (Viagra and Cialis) were obtained from UPLC-MS data. Methanol extracts of crushed tablets were investigated by ultra performance liquid chromatography (UPLC) with diode array detection (DAD) coupled with eletrospray ionization in the positive ion mode (ESI(+)) quadrupole time-of-flight (Q-Tof) mass spectrometry (MS). A validated method was employed for the simultaneous determination of sildenafil citrate (SLD) and tadalafil (TAD). The ultra-chromatograms obtained with method provide high resolution of MS, and are a quick (less to 1.5 min) and reliable tool in the distinction between authentic and counterfeit tablets. It was observed in most cases the presence of other active pharmaceutical ingredients (APIs) than specified on the package (TAD and SLD). Additionally, high concentrations of TAD and SLD were detected in counterfeit samples when compare with observed values for a typical commercial product. Chemometric methods were employed and the samples were grouped in five groups as function of API content. (C) 2013 Elsevier Ireland Ltd. All rights reserved.