A surface enhanced Raman scattering quantitative analytical platform for detection of trace Cu coupled the catalytic reaction and gold nanoparticle aggregation with label-free Victoria blue B molecular probe.

With development of economy and society, there is an urgent need to develop convenient and sensitive methods for detection of Cu pollution in water. In this article, a simple and sensitive SERS sensor was proposed to quantitative analysis of trace Cu in water. The SERS sensor platform was prepared a common gold nanoparticle (AuNP)-SiO sol substrate platform by adsorbing HSA, coupling with the catalytic reaction of Cu-ascorbic acid (HA)-dissolved oxygen, and using label-free Victoria blue B (VBB) as SERS molecular probes. The SERS sensor platform response to the AuNP aggregations by hydroxyl radicals (•OH) oxidizing from the Cu catalytic reaction, which caused the SERS signal enhancement. Therefore, by monitoring the increase of SERS signal, Cu in water can be determined accurately. The results show that the SERS sensor platforms owns a linear response with a range from 0.025 to 25μmol/L Cu, and with a detection limit of 0.008μmol/L. In addition, the SERS method demonstrated good specificity for Cu, which can determined accurately trace Cu in water samples, and good recovery and accuracy are obtained for the water samples. With its high selectivity and good accuracy, the sensitive SERS quantitative analysis method is expected to be a promising candidate for determining copper ions in environmental monitoring and food safety.