Affinity driven ion exchange EG-OFET sensor for high selectivity and low limit of detection of cesium in seawater

The detection and quantification of Cs+ in aquatic media are an environmental safety public health matter, so far limited by the lack rapid, low cost, limit selective analytical tools. Herein we demonstrate efficient fabrication a novel electrolyte-gated organic field-effect transistor sensor for seawater based on combination two ultra-thin layers namely poly(3-hexylthiophene) as semiconductor single lipids monolayer dielectric. latter is end-capped with specific probe calix[4]arene benzocrown ether to ensure selectivity. Interestingly, clearly evidence that controlling affinity driven guest/host ion exchange, one can lift general problem selectivity encountered all FET-based sensors, reaching nearly perfect even highly complex analyte solutions containing competitive ions, such phosphate buffered saline solution or seawater. Such structure exhibits, at sub-femtomolar level which corresponds 5 folds’ magnitude lower than Inductively Coupled Plasma Mass Spectroscopy, most commonly used technic today. These results pave way generalized monitoring complexed analytes.