The availability of pharmaceuticals to treat and to prevent disease has brought great benefit. Nevertheless, attention is being drawn to the uncontrolled use and careless disposal of medications for humans and animals. These compounds and their metabolites are found in the environment and foodstuffs, with possible adverse risks to human health. Detection of pharmaceuticals and residues in environmental and biological matrices has become a priority for governmental agencies. However, current analytical methods capable of detecting pharmaceuticals at very low levels require time-consuming sample preparation, concentration and/or extraction prior to analysis. Biosensors offer several advantages over existing techniques (e.g., less time, high-throughput screening, improved sensitivity, real-time analysis and the possibility of developing label-free detection methods and devices). Also, incorporation of nanotechnology into biosensor systems may increase the speed and the capability of the diagnostic methods. Moreover, the possibility of using biosensor systems in different configurations allows us envisaging their implementation as point-of-care systems or multiplexed devices. This review provides a general overview of the progress, the limitations and the future challenges of biosensors for detecting pharmaceuticals. (C) 2011 Elsevier Ltd. All rights reserved.
