In the last decade, the trafficking and use of illicit drugs showed a continuous incremental trend, remaining worldwide a challenging problem for the consequences on society, health, criminality, and environment. The introduction on the market of new products and of illicit synthetic compounds represents a new challenging task for analytical chemistry, looking for rapid and accurate methods for the detection of illicit substances in seized street samples, biological fluids, and wastewater. In this context, electrochemical sensors have shown promising results as an alternative to standard chromatographic and spectroscopic methods. This review aims at highlighting the most recent progresses in the use of electrochemistry for the detection of drugs of abuse, mainly including well consolidated substances like cannabinoids, cocaine, opioids, ecstasy, and methamphetamine as well as new psychoactive molecules widely diffused at the present time. Different strategies have been described particularly consisting in the direct electrochemical oxidation of the target analyte. The implementation of tailor-made portable instruments with electrochemical detection methods constitutes an added value to improve the effectiveness of electrochemical sensors for the identification of psychoactive substances when performing large-scale sampling tests.
相似文献Multilayers consisting of a water soluble polythiophene derivative and Au nanoparticles have been deposited onto different electrode substrates by means of layer-by-layer deposition technique. The assembly of the films has been performed by taking advantage of the electrostatic interactions between the positively charged imidazolic moiety of the polythiophene chain and the negative charges of citrate ions surrounding Au nanoparticles, as well of the affinity of S to Au. The nanoparticles result stably grafted to the organic matrix. The resulting modified electrodes have been characterised through electrochemical, spectroelectrochemical and microscopic techniques. The results evidenced that a high number of individual nanoparticles is present inside the multilayer. The presence of nanoparticles is of chief importance for most effective charge percolation through the multilayer, as suggested by the responses to electroactive probe species in solution. The electrocatalytic performances of the modified electrodes have been tested with respect to the oxidation of ascorbic acid.
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