Journal of Analytical & Bioanalytical Techniques
Open Access

Abstract

Counterfeit medicines are introduced as a worldwide problem but with regional emphasis focused on different disease states. The occurrence of counterfeits ranges from 1-2% in the UK to 30-40% in some African countries. According to the WHO counterfeits medicines may have: no active pharmaceutical ingredients (API) present, the wrong level of API, the wrong API, high levels of contaminants or be in counterfeit packaging. The different analytical approaches to identifying counterfeit medicines are discussed in terms of instrumental complexity and analysis time. The usability of the different systems under real world conditions are discussed and lead to the potential of Attenuated Total Reflection (ATR) FT/IR techniques to provide rapid quantitative investigations of suspect tablet formulations. ATR FT/IR methods require only that the tablet be crushed prior to analysis providing a considerable time saving over the solvent extraction protocols used by the British Pharmacopoeia. Standard spectra of API plus excipients, from crushed tablets, were recorded for identification purposes and quantitative data was obtained from spectra of calibrated mixtures of the API and excipients. The APIs studied include paracetamol, atenolol, aspirin and caffeine with a range of different excipients. Tablet samples from various countries including India, Pakistan, Saudi Arabia 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 but there were considerable discrepancies in the levels of API in the atenolol tablets. This was confirmed by conventional extractive analyses. ATR FT/IR can therefore identify counterfeit tablets rapidly without the need for solvents. Whilst LC MS/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 which impact on patient health and contribute to the increase in drug resistant species.

Biography

Graham Lawson is a Principal Lecturer in Forensic Analysis in the Leicester School of Pharmacy at De Montfort University. His expertise and research interests lie in the application of various instrumental analytical techniques to the identification and quantification of toxic and other species in a variety of matrices: blood, water, food etc. This has led to the development of micro-analytical methodologies based on LC-MS and LC-HRMS studies (awarded the Royal Society of Chemistry Analytical Methods Prize in 2010) complimented by new ATR FT/IR spectroscopic investigations