Sensitive and simple sonoluminescence detection of melamine via aggregation of Au nanoparticles

Abstract

In this work, we report a novel Au nanoparticle-sonoluminescence (AuNP-SL) design for simple and high throughput detection of melamine with a lab-made SL vial. Aqueous SL at 520 nm can be sensitively quenched and restored by dispersed and aggregated AuNPs, respectively. Based on this, the melamine-induced aggregation state of AuNPs is characterized by measuring the SL variation, as well as the content of melamine. All the ultrasound parameters and experimental variables, including the duration and interval of ultrasound irradiation, the composition of the test solution, and the melamine–AuNP interaction time, were separately investigated and optimized. The established SL method exhibits a good linear SL response to melamine concentrations in the range of 10 to 240 nM with a limit of detection (3σ) of 3 nM. The proposed method has been applied to the quantification of melamine in milk products. Statistical analysis results from F and t tests demonstrated the agreement between the SL method and the official method both in precision and accuracy.