Potential Recognition Layer in Electrochemical Sensor: A Comparative Characterization of p-Cyano Schiff Base Compounds

Abstract

The effective conjugation of electrons in aromatic Schiff bases has been utilized as an electrochemical sensor in forensic, pharmaceutical and environmental applications. The use of the Schiff base enhances the sensitivity and selectivity of the sensor. In this study, p-cyano Schiff base derived from 4-(4-aminostyryl)benzonitrile and three different aldehydes were synthesized. The spectroscopic techniques via Fourier transform-infrared spectroscopy (FT-IR), Uv-Vis spectrophotometry and Nuclear Magnetic Resonance (NMR) of 1H and 13C were used for structural elucidation resulted compounds. The targeted p-cyano Schiff base showed a clear imine (C=N) stretching vibration band at 1681-1708 cm-1, n→π* electronic transition at 355-360 nm in UV-Vis and a singlet: 8.34-8.39 ppm and 118.07-119.09 ppm for 1H and 13C NMR, respectively, supporting the formation of Schiff bases. The application of Schiff base as spacer in electrochemical DNA (E-DNA) sensor has not been much research done on it so far. The obtained compounds are potentially valuable for electrochemical-DNA sensor study in the future.