Development of a thickness shear mode acoustic sensor based on an electrosynthesized molecularly imprinted polymer using an underivatized amino acid as the template

Abstract

The preparation and characterization of electrosynthesized poly(o-phenylenediamine) (iPoPD) as a molecular imprinting material were studied by an in situ quartz crystal impedance method. The changes of Δf₀, ΔR₁, ΔL₁ and ΔC₀ suggest that the polymer film was compact and rigid. The thickness shear mode (TSM) acoustic sensor modified with this material exhibits molecular recognition ability to the template molecule of DL-phenylalanine. In the range 2–20 mM, a linear relationship between the frequency shift Δf₀ and logC was found from the calibration graph. Scatchard analysis of the relevant calibration graph offers information on the equilibrium of the binding interaction and the recognition sites. Using this electropolymerization technology, the preparation of the sensor was very simple and the reproducibility of preparation was very good. In particular, it offers possibilities for sensor miniaturization.