Uncovering Counterfeit Viagra and Cialis Using Portable NIR and UV-Visible Spectroscopy Coupled with Multivariate Data Analysis (a preliminary study)

In this study, two of the most common drugs (Cialis® and Viagra®) that are subjected to adulteration were investigated. The investigation involved examining the above drugs using both portable NIR and UV-Visible spectroscopy. The obtained spectral data were analyzed using multivariate chemometric methods such as Principal Components Analysis (PCA) and Cluster Analysis (CA). Discriminating between the original and the counterfeit drugs was successfully demonstrated with no or little chemical pretreatment. Detection of counterfeit drugs from different sources was also possible.