Visual Detection of Melamine in Urine Based on an AuNPs-Curcumin System

Abstract

A colorimetric method involving a novel gold nanoparticle-curcumin system is described for determination of melamine in urine. The natural phenol curcumin can reduce chloroauric acid to form well-dispersed gold nanoparticles, while at high concentration of melamine, reduction is suppressed and blue aggregates are quickly formed, which is confirmed by UV-vis spectroscopy and TEM images. The ratio of absorbances at 673 and 546 nm increases linearly in the 0.5 to 4 ppm melamine concentration range, and the detection limit is 0.16 ppm. The assay has been applied to analyze urine samples and showed recoveries with RSDs of <5%. The gold nanoparticle-curcumin based analytical system is simple for one-pot synthesis, convenient for visual detection and rapid requiring only 30 min. Therefore, it is a promising assay approach for melamine adulteration and well suited for homecare testing.

Nanoarchitectonics for Analytical Science at Interfaces and with Supramolecular Nanostructures

“…Chen and co-workers reported visual detection of melamine in urine using gold nanoparticles with curcumin nanoarchitectonics. 96 Natural phenol curcumin efficiently reduced chloroauric acid resulting in the formation of well-dispersed gold nanoparticles. The presence of melamine suppressed the reduction to gold accompanied with the formation of blue aggregates (Fig.…”