Electrochemical Detection of Drugs via a Supramolecular Cucurbit[7]uril-Based Indicator Displacement Assay
Nilima Manoj Kumar, Patrick Gruhs, Angela Casini, Frank Biedermann, Guillermo Moreno‐Alcántar, Pierre Picchetti
Abstract
High Resolution Image Download MS PowerPoint Slide Electrochemical detection methods are attractive for developing miniaturized, disposable, and portable sensors for molecular diagnostics. In this article, we present a cucurbit[7]uril-based chemosensor with an electrochemical signal readout for the micromolar detection of the muscle relaxant pancuronium bromide in buffer and human urine. This is possible through a competitive binding assay using a chemosensor ensemble consisting of cucurbit[7]uril as the host and an electrochemically active platinum(II) compound as the guest indicator. The electrochemical properties of the indicator are strongly modulated depending on the complexation state, a feature that is exploited to establish a functional chemosensor. Our design avoids cumbersome immobilization approaches on electrode surfaces, which are associated with practical and conceptual drawbacks. Moreover, it can be used with commercially available screen-printed electrodes that require minimal sample volume. The design principle presented here can be applied to other cucurbit[ n ]uril-based chemosensors, providing an alternative to fluorescence-based assays.