RAMAN SUPPLEMENT


Suspect medicine


In the lab: • Correlation with database • Classification methods (ex: SVM)


Authentication of the product In the field:


First screening with handheld spectrometers


STEP 1 Genuine product Or Counterfeit


Further chemical analyses (in the lab)


• Interpretation of Raman spectra • Infrared spectroscopy • NMR


• GC-MS, LC-MS STEP 2


Determination of chemical composition


Chemical profiling


Comparison with previous counterfeits (ex: PCA)


Classification of counterfeits Evaluation of hazard


Forensic investigation


Combination with seizure and packaging information Sourcing of new counterfeits


STEP 3


Information for law enforcement


FIGURE 1Proposed strategy for the analysis of counterfeit medicines by Raman spectroscopy. The three steps of analysis consist in the detection, the determination of chemical composition and the chemical profiling of counterfeits


Raman spectroscopy is non-destructive and only needs a limited sample preparation. Capsules sometimes need to be opened so that fluorescence can be avoided. The coating of some tablets is also preferably scraped so that the laser can reach the core in order for the peaks of the compounds to be observed. Counterfeits can moreover be measured


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European Pharmaceutical Review Volume 16 | Issue 5 | 2011


through transparent packaging like glass, plastic bags or blisters.


Detection of counterfeits by Raman spectroscopy The authentication of medicines by Raman spectroscopy, constituting the first step of the process (Figure 1), can be performed


using several interpretation and statistical methods. The easiest consists of comparing the spectrum of the suspect product with the reference medicine and for more assurance, with the spectrum of the genuine API too (Figure 2, opposite). A correlation calculated between the spectra of suspect and reference products can


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