aikemy

Abstract

The miniaturized Near-Infrared Spectroscopy (NIRS) enables convenient, non-destructive, and real-time testing of medicines circulating on the field or throughout the supply chain. We have successfully been able to detect falsified Viagra using a new low-cost, consumer-type NIRS. In like manner, we have distinguished the original Viagra from its generic versions with the same dose. This innovation is a promising way of ensuring medicines authenticity by looking at their chemical ‘fingerprints’. Portable screening technologies for medicine quality assurance on the field or throughout the supply chain are currently growing and complementing the current approach for combating the falsified products, i.e., safety features on the packaging and laboratory analysis of suspect samples. In total, 78 spectra of Sildenafil-based tablets were recorded and classified using the K-Nearest Neighbors algorithm that relies on the Euclidean distances between measured values. The accuracy of our model was assessed using cross-validation and bootstrapping techniques. As a result, the miniaturized NIRS correctly ordered all tablets according to their manufacturer and indicated the falsified tablets. The spectra differed in shape from the authentic versions and show the high spread in chemo-physical characteristics, which suggest poor manufacturing practices of the falsified products.