Raman spectroscopy and hierarchical cluster analysis for the ingredients characterization in different formulations of paracetamol and counterfeit paracetamol

The distribution of pharmaceutical ingredients in tablet influences its effectiveness. Direct analysis of tablet using Raman spectroscopy generates information on internal distribution of tablet ingredients. Raman spectra of local and imported formulations of paracetamol clearly discriminated signatures of paracetamol and caffeine in Panadol and Panadol Extra respectively in intact, sliced and powdered tablets/caplets. The presence of few excipients like titanium dioxide in surface coating and calcium carbonate was also detectable in imported Panadol Advance and Panadol Extra caplets with Optizorb (R) technology which helps in quick disintegration of tablet inside body. Moreover, locally available counterfeit paracetamol was also analysed that showed less intense peaks for active ingredient i.e. paracetamol and few enhanced peaks for excipients as separated by hierarchical cluster analysis (HCA). It is suggested that Raman spectroscopy alongwith chemometrics can be effectively used for the rapid identification and distribution of active drug ingredients in tablets for quality control and detection of counterfeit drugs.