Zeitschrift für analytische und bioanalytische Techniken

Abstrakt

Counterfeit Tablet Investigations: Can ATR FT/IR Provide Rapid Targeted Quantitative Analyses?

Graham Lawson, John Ogwu and Sangeeta Tanna

Counterfeit medicines are now a global public health problem. In developed countries up to 1% of medicines are reported to be counterfeit whilst in developing countries the level is ~30-40%. In this research the potential of Attenuated Total Reflection (ATR) FT/IR techniques to provide rapid quantitative analyses of suspect tablet formulations is reported. Unlike conventional tablet analyses where several tablets are crushed and solvent extracted, ATR FT/IR methods require that only a single tablet be crushed prior to analysis. This provides a considerable time saving over the solvent extraction protocols cited in the British Pharmacopoeia. Reference ATR FT/IR spectra of the active pharmaceutical ingredient (API) and excipients, from crushed tablets, were recorded for identification purposes. Quantitative data was obtained from ATR FT/IR spectra of calibrated mixtures of the API in the excipients. Tablet samples from various countries, India, Africa, China, Belgium and the UK were examined. Initial results showed the API could be identified down to ca 5% w/w of the tablet. Quantification was linear with selected characteristic peak areas for each API/excipient mixture. The analysis of the tablet samples generally showed good agreement with expectation. This was confirmed by conventional extractive analyses followed by UV quantification. ATR FT/IR can therefore identify counterfeit tablets rapidly without the need for solvents. Whilst LCMS/ MS and NMR techniques may be the ‘gold standards’ of the analytical world they are of much reduced value in sub-Saharan African countries whereas a portable ATR FT/IR may prevent the use of counterfeit antimalarial tablets and contribute to improvements in patient health.