The fluorescence quenching of rhodamine 6G as an alternative sensing strategy for the quantification of silver and gold nanoparticles

Abstract

A method for the quantification of 22–26 nm gold (AuNP) and 10–20 nm silver nanoparticles (AgNP) was developed using the fluorescence quenching of rhodamine-6G. This fluorescent probe detected the different metal nanoparticles (MNP) at the pmol L−1 level (3.6 to 15.6 pmol L−1) depending on the type of nanoparticle) in phosphate buffer solutions at pH 6.94. The method was validated at the 95% confidence level using recovery tests to spiked drinking and surface river water (before and after industries). For AuNP26@citrate and AgNP12@SDDC, the overall average recoveries (R¯) were 90% (RSD: 11%) and 82% (RSD: 10%) in drinking water, respectively. Whereas, in surface river water before and after industries, R¯ were 88% (RSD: 17%) and 93% (RSD: 11%) for AuNP26@citrate, correspondingly; and 94% (RSD: 6%) and 83% (12%) for AgNP12@SDDC, respectively. The proposed strategy represents an accurate, rapid, simple, and cost-effective methodology to analyze MNP in aqueous systems.