Synthesis and characterization of gold nanostars and their evaluation in the SERS detection of pesticides

Abstract

In this research project, we propose the study of the synthesis and characterization of gold nanostars (AuNSs) for their application in the detection of pesticides by surface-enhanced Raman spectroscopy (SERS). The synthesis of AuNSs will be studied systematically by two methods: with and without the use of precursor seeds, where the comparison of these methods will be made in terms of sensitivity and repeatability of the SERS signal generated. The characterization studies will be carried out using scanning and transmission electron microscopy techniques, and UV-visible spectroscopy, aiming to identify reproducible synthesis conditions (i.e., homogeneity in the size and shape of the AuNSs). Finally, the fabricated SERS substrates based on paper coated with AuNSs will be applied in the detection of pesticides, such as chlorpyrifos, thiabendazole, thiram, carbendazim and malathion. These studies will be carried out considering performance parameters such as detection and quantification limits, sensitivity, repeatability, correlation coefficient, accuracy, and precision. The results will provide a better understanding of the influence of the chemical structure of the pesticides on their detection using SERS. It is expected that the proposed nanomaterials and sensors contribute to the efforts to establish SERS as a general analytical strategy for environmental protection.