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Evaluation of the residual solvent content of counterfeit tablets and capsules
E Deconinck1, M Canfyn, P-Y Sacré
1Division of Food, Medicines and Consumer Safety, Section Medicinal Products, Scientific Institute of Public Health (WIV-ISP), J. Wytmansstraat 14, B-1050 Brussels, Belgium. Eric.Deconinck@wiv-isp.be
Abstract:
A group of counterfeit samples of Viagra and Cialis were screened for their residual solvent content and compared to the content of the genuine products. It was observed that all counterfeit samples had higher residual solvent contents compared to the genuine products. A more diverse range of residual solvents was found as well as higher concentrations. In general these concentrations did not exceed the international imposed maximum limits. Only in a few samples the limits were exceeded. A Projection Pursuit analysis revealed clusters of samples with similar residual solvent content, possibly enabling some future perspectives in forensic research.
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