Sensitive turn-on fluorescent detection of melamine based on fluorescence resonance energy transfer

Abstract

We here report a novel fluorescent method for the detection of melamine based on the high fluorescence quenching ability of gold nanoparticles. The fluorescence was significantly quenched via fluorescence resonance energy transfer when fluorescein molecules were attached to the surface of gold nanoparticles by electrostatic interaction. Upon addition of melamine, the fluorescence was enhanced due to the competitive adsorption of gold nanoparticles between melamine and fluorescein. Under the optimum conditions, the fluorescence enhancement efficiency [(I-I(0))/I(0)] showed a linear relationship with the concentration of melamine in the range of 1.0 × 10(-7) mol L(-1)~4.0 × 10(-6) mol L(-1), and the detection limit was calculated to be 1.0 × 10(-9) mol L(-1). The proposed method showed several advantages such as high sensitivity, short analysis time, low cost and ease of operation.

Validation of a method of high performance liquid chromatography with fluorescence detection for melamine determination in UHT whole bovine milk

“…Some new methods based on luminescence phenomena were proposed recently for the determination of melamine: complexation with a fluorescent sensor (cucurbit-7-uryl, for example) (Zhou, Yang, Liu, Wang, & Liu, 2010), electroluminescence enhancement of Ru(bpy) 3 2þ (Guo, Gai, et al, 2011), resonance energy transfer and fluorescence enhancement by gold nanoparticles (Guo, Zhong, et al, 2011;Xiang, Zeng, Zhai, Li, & He, 2011) and the use of the Mannich reaction (Rima, Assaker, Omar, & Karim, 2013). However, none of these studies employed measurements of the natural fluorescence of melamine, as recently shown and applied for its determination in kitchen plastic ware (Finete, Gouvêa, Marques, & Pereira Netto, 2014).…”

Rapid determination of melamine in milk using water-soluble CdTe quantum dots as fluorescence probes

“…To date, several fluorescent methods have been reported for the detection of melamine Attia et al 2011;Guo et al 2011;Xiang et al 2011). To our knowledge, there has been no previous report on QDs-based luminescent probes for the detection of melamine in food.…”

“…In addition, melamine in milk powder could be detected based on the fluorescence enhancement of Au NPs (Xiang et al 2011). A sensitive ''turn-on'' fluorescent method for the detection of melamine has been developed by utilising Au NPs as a highly efficient quencher (Guo et al 2011).…”

Sensitive fluorescent detection of melamine in raw milk based on the inner filter effect of Au nanoparticles on the fluorescence of CdTe quantum dots

“…Au and Ag nanoparticles (NPs) have been extensively used as colorimetric probes for melamine sensing in liquid milk and infant formula owing to their unique size-dependent and interparticle-distance dependent optical properties and the accompanying color change of solution (Guo et al, 2010;Li, Li, Cheng, & Mao, 2010;Ping et al, 2012). A sensitive turn-on fluorescent detection method for melamine has been developed through its modulation on the efficiency of fluorescence resonance energy transfer (FRET) between Au nanoparticles (AuNPs) and fluorescein (Guo et al, 2011). Quantum dots (QDs) display superior luminescent properties, including high quantum yield of fluorescence, broad excitation spectrum, narrow/symmetric emission spectrum, size-and composition-tunable emission wavelength, high photobleaching threshold and excellent photostability.…”