Novel multifunctional molecular recognition éléments based on molecularly imprinted poly (aniline-co-3,4-ethylenedioxy-thiophene) composite thin film for salicylamide electrochemical detection.

Abstract

The combination of co-electropolymerization and molecularly imprinting technology provides functional materials with improved properties and can enhance the number of binding sitesthan the individual monomer. In this work, molecularly imprinted poly (anilineco-3,4-ethylenedioxy-thiophene) MI-P(AnEDOT) composite thin film was synthesized on gold electrode by using an in-situ co-electropolymerization method using salicylamide (SMD) as a template. The formation of the thin film was monitored and characterized by electrochemical methods; SWV and CV. Solvent extraction of the template generated the binding cavities in the polymer matrix which fit the target in size, shape and functionality. After the rebinding of SMD, the novel sensor shows a linear range between 2 × 10-6 to 1 × 68.5 ppm, limit of detection (LOD) of 7.88 × 10-6 ppm. The composite film showed high affinity towards SMD through multiple noncovalent interactions, good stability and reproducibility with RSD 2.1 %. The developed sensor has an interesting potential for real sample testing applications with good RSD of 6.01 % and a LOD of 9.29 × 10-6 ppm. The new sensing composite material has great sensitivity and selectivity due to the synergistic effects of multi-functionality from the two polymers, porous thin film and imprinting effect. To this end, the MI-P(AnEDOT) can be regarded as a potential functional material for the chemical sensor development in future.