Abstract Raman spectroscopy, one of the most widely used optical spectroscopic technique can provide molecular information about pharmaceutical drugs. This particular spectroscopic technique has proven its potential over the others by overcoming the barriers faced in traditional approaches and by providing unique benefit of molecular characterization in near real time. In this spectroscopy method, incident light interacts with the molecule inelastically and the scattered light has specific vibration modes of molecules in form of sharper Raman peaks. The technique thus can identify the molecular structure of the given tablet sample. Since the sample used for Raman measurements can be reused, it can provide a non-destructive way of analyzing. There are two different configurations of Raman spectroscopy: (1) back-scattered and (2) transmission. In back-scattered Raman spectroscopy, tablet is illuminated using a laser source and the Raman’s back-scattered from the tablet surface is collected for the detection. In contrast, transmission Raman spectroscopy (TRS) collects Raman signals transmitted through the tablet sample. While back-scattered Raman signal is only originated from the superficial depths though with excellent signal to noise ratio (SNR), transmission Raman signal can be obtained through the whole tablet, however with lower SNR. This report presents the results of the Raman spectral measurements of binary NSAID drug, paracetamol-ibuprofen using both the configurations of Raman spectroscopy. Both the configurations could reveal identical signatures. Owing to better SNR, back-scattered Raman spectroscopy is suggested as a potential tool for API determination of binary NSAID paracetamol-ibuprofen drug.
Keywords Paracetamol Tablet, Ibuprofen Tablet. Transmission Raman spectroscopy, Back scattered Raman spectroscopy.