Picosecond laser-assisted synthesis of silver nanoparticles with high practical application as electroanalytical sensor

Abstract

Gallic acid (GA) is one of the most important and present natural phenolic compounds due to its well-known biological properties, and its detection and monitoring is of great importance. Silver nanoparticles (AgNPs) are one of the most studied metallic nanomaterials used in various fields, from biomedical applications to electrochemical sensing devices. In this work, we used the pulsed laser ablation technique in liquid for the one-step preparation of nanoparticles of silver from a pure silver plate base in N,N-dimethylformamide. Obtained nanomaterial was characterized using morphological and electrochemical methods and used for modification of screen-printed carbon electrodes (SPCE). Successful immobilization at the surface is confirmed using the surface profiling method. A newly obtained sensor was used for the detection of GA. After parameters optimization, a differential pulse voltammetric protocol was developed, using two approaches - concentration vs. current (GA determination) and peak area vs. current (estimation of the antioxidant capacity). For the first approach sensor linearity was found to be in the range from 0.50 µM to 10 µM, with the limit of detection (LOD) of 0.16 µM and limit of quantification (LOQ) of 0.50 µM. In the second system operating linear range was the same, while LOD and LOQ were 0.11 µM and 0.34 µM, respectively. Practical application of the method was tested using two approaches: direct measurement of gallic acid in biological fluids and estimation of the antioxidant capacity and food quality purpose.