Design of chemoresistive sensory materials: polythiophene-based pseudopolyrotaxanes.

The authors report conducting polymer-based sensors which transduce reversible, noncovalent, and non-redox-dependent mol. recognition events into measurable changes in cond. These chemoresistive polymers are derived from bithiophenes contg. cyclophane receptors capable of forming self-assembled pseudorotaxane complexes with paraquat. The electrostatic perturbations arising from pseudopolyrotaxane formation cause a decrease in carrier mobility and thus lower the cond. The chemoresistive response was consistent with decreased carrier mobility and exhibited an enhanced sensitivity to analyte-promoted electrostatic perturbations relative to the voltammetric response. Polymer-based devices which demonstrate a real time chemoresistive response to paraquat are also reported. [on SciFinder(R)]