Authentication of medicines using Raman spectroscopy

Raman spectroscopy offers a rapid and non-destructive technique for the identification of counterfeit medicines. Handheld Raman instruments offer the advantages of carrying the laboratory to the sample and giving a rapid pass or fail answer for the medicine inspected. It can identify a medicine regardless of its physical form to tablet, powder, ointment, cream or liquid. However, the technique is limited as not all species of a medicine have a Raman scattering. Thus, the Raman spectrum obtained upon measuring a medicine might be due to the active pharmaceutical ingredient or any other excipient in the bulk or the coating of the formulation. In addition, the Raman spectra of some species might not be detected in the reflection mode. In this respect, the use of laboratory based instruments in transmission mode can be used for the measurement of these medicines. Thus, both handheld and laboratory based instruments are complementary for the authentication of medicines detection. An initial scanning could be carried out using the handheld instrument and the suspected counterfeit medicines could be taken to the laboratory and further analysed using laboratory based instruments.