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Mimicking Nature's polymeric protein architectures by designing hosts with binding cavities screened from bulk solvent is a promising approach to achieving anion recognition in competitive media. Accomplishing this, however, can be synthetically demanding. Herein we present a synthetically tractable approach, by directly incorporating potent supramolecular anion‐receptive motifs into a polymeric scaffold, tuneable through a judicious selection of the co‐monomer. A comprehensive analysis of anion recognition and sensing is demonstrated with redox‐active, halogen bonding polymeric hosts. Notably, the polymeric hosts consistently outperform their monomeric analogues, with especially large halide binding enhancements of ca. 50‐fold observed in aqueous‐organic solvent mixtures. These binding enhancements are rationalised by the generation and presentation of low dielectric constant binding microenvironments from which there is appreciable solvent exclusion. [ABSTRACT FROM AUTHOR]

The development of real‐life applicable ion sensors, in particular those capable of repeat use and long‐term monitoring, remains a formidable challenge. Herein, we demonstrate, in a proof‐of‐concept, the real‐time voltammetric sensing of anions under continuous flow in a 3D‐printed microfluidic system. Electro‐active anion receptive halogen bonding (XB) and hydrogen bonding (HB) ferrocene‐isophthalamide‐(iodo)triazole films were employed as exemplary sensory interfaces. Upon exposure to anions, the cathodic perturbations of the ferrocene redox‐transducer are monitored by repeat square‐wave voltammetry (SWV) cycling and peak fitting of the voltammograms by a custom‐written MATLAB script. This enables the facile and automated data processing of thousands of SW scans and is associated with an over one order‐of‐magnitude improvement in limits of detection. In addition, this improved analysis enables tuning of the measurement parameters such that high temporal resolution can be achieved. More generally, this new flow methodology is extendable to a variety of other analytes, including cations, and presents an important step towards translation of voltammetric ion sensors from laboratory to real‐world applications. [ABSTRACT FROM AUTHOR]