Identification of Adulterated PDE5 Inhibitors by Confocal Raman Microscopy

OBJECTIVE To develop a Raman spectroscopy method for the identification of PDE5 inhibitors adulterated in traditional Chinese medicines.METHODS The spectra of the samples,collected by Confocal Raman microscopy with the spatial mapping and multivariate analysis of Raman maps,were compared with those obtained with the reference substances.RESULTS The PDE5 inhibitors such as Sildenafil and Tadalafil adulterated in the products supplied for inspection were rapidly detected.The results were further verified by HPLC-MS analysis.CONCLUSION The Confocal Raman microscopy can be used as an alternative method for the identification of the adulteration of traditional Chinese medicines and health-care food with synthetic drugs.