Tuning of the surface structure of silver nanoparticles using Gum arabic for enhanced electrocatalytic oxidation of morin

Abstract

Gum arabic stabilized silver nanoparticles have been used to modify carbon paste electrodes (AgNPs-GA/CPE) for the electrochemical sensing of morin, a flavanoid. The synthesized nanoparticles, before and after modification of electrodes were characterized by UV–visible spectroscopy, X-ray diffraction (XRD), fourier transformation infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential measurements, and thermogravimetric analysis (TGA). The uniform-sized spherical silver nanoparticles have particle sizes less than 10 nm. AgNPs-GA/CPE electrode has shown excellent electrocatalytic activity towards the oxidation of morin at a potential of 0.14 V. The factors influencing the electrochemical determination of morin such as the effect of pH, the effect of scan rate, and the effect of concentration were studied in detail. The linear dynamic range was found to be 0.65 nM to 7.0 nM with a detection limit of 0.216 nM. The developed sensor has been successfully applied for the determination of morin in mulberry leaves and almonds.

Keywords

• Gum arabic
• Silver nanoparticles
• Carbon paste electrode
• Morin
• Electro-oxidation