Counterfeit drugs, detection

T. Moffat, R. Watt, and S. Assi, NIR-Based Approach to Counterfeit-Drug Detection, Spectrosc. Eur., 22,6 (2010). 

Another important analytical area includes the noninvasive detection of counterfeit drugs, through the plastic or glass bottles and blister packs in which they are... 

A considerable amount of (unpublished) work has been performed by Ciurczak on counterfeit tablets. Using the same algorithms that have been applied to discriminate between placebos and active products, counterfeit products may be easily identified. The spectral variability stems from different raw materials and manufacturing processes, even though the active may be present at the correct level. Moffat et al. [49], Rodionova et al. [50], and Polli et al. [51] published examples of use of NIR to detect counterfeit drugs. 

The power of NIRS to detect counterfeit drugs was investigated by Scafi and Pasquini [2] with a large variety of real samples of counterfeit dmgs. These authors reported that their NIRS application was able to recognize all those counterfeit drugs that differed in composition... 

Chapters 2 and 3 have been replaced (Basic Principles and Theories of Diffuse Reflection), several chapters (4,19,25,26,29, and 37) have been updated (Commercial Instrumentation, Analyses of Textiles and of Baked Products, Advances in the Petrochemical Industry, Polymers, Pharmaceutical Applications, and Process Analysis), and some new chapters (12,18,21,28,29,31,32,33,35, and 38) have been added (Process Sensors, Agro-Forestry Systems, Gas Analysis, Use of NIR at the Bowling Alley, PAT in the Pharmaceutical Industry, Nutraceuticals, Detection of Counterfeit Drugs (e.g., Viagra), NIR Photography in Medicine, Biomedical Components in Blood and Semm, and The Detection of Counterfeit Currency and Turquoise). 

ICP-MS has been employed, as discussed in Section 9.5, for the determination of platinum originating from cisplatin, carboplatin and oxaliplatin in human plasma ultrafiltrate. The method developed was successfully used to support pharmacokinetic studies in cancer patients treated with cisplatin, carboplatin or oxaliplatin.5 Counterfeit products on the drug market, which have important implications for pharmaceutical companies and human health, can be clarified by mass spectrometric isotope ratio measurements. For example, precise and accurate sulfur isotope measurements (a 54S) by MC-ICP-MS, were employed to study the isotope variation of pharmaceuticals and to detect to the origin of counterfeits by Clough el al.6... 

In 1999, WHO published guidelines on the detection and prevention of counterfeit and substandard products. Vigilance and reporting of counterfeit products to WHO were enhanced by setting up a liaison officer network among drug regulatory authorities and WHO. 

The main use of TLC in analysis of amoxicillin and its formulated products is as an identity test. A major study [105] using silica gel and silanised silica gel plates with thirty five different mobile phases and iodine vapour detection produced a system, on silanised plates with ammonium acetate/acetone mobile phase, in which amoxicillin was separated from all the other penicillins studied. A slightly modified version of this system was subsequently introduced into the European and British Pharmacopoeia monographs for amoxicillin trihydrate and sodium salt [2]. The British [57,58] and US [9] Pharmacopoeias specify other TLC systems for identification of amoxicillin in formulated products. Simple TLC methods have been developed for identification of several compounds on the WHO essential drugs list, to help combat counterfeiting [106]. For amoxicillin, systems using ethyl acetate/acetic acid/water or acetone/toluene/acetic acid/water with silica gel plates were recommended. 

Santamaria-Fernandez, R., Hearn, R., Wolff, J-C. (2009) Detection of counterfeit antiviral drug Heptodin and classification of counterfeits using isotope amount ratio measurements by multicollector inductively coupled plasma mass spectrometry (MC-ICEMS) and isotope ratio mass spectrometry (IRMS). Sci. Justice, 49(2), 102-106. 

Santamaria-Femandez, R., Heam, R., and Wolff J.C. (2008) Detection of counterfeit tablets of an antiviral drug using measurements by MC-ICP-MS and confirmation by LA-MC-ICP-MS... 

Dingari et al developed an SVM toolbox to be coupled to LIBS to screen drugs and detect counterfeit samples. Examples were presented where SVM improved other classical classification methods, such as SIMCA and PLS-DA. 

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