Colorimetric Determination of Melamine in Dairy Products by Fe₃O₄ Magnetic Nanoparticles−H₂O₂−ABTS Detection System

Abstract

In this paper, a simple and rapid colorimetric method, which does not require any expensive and complex instruments, is established for the determination of melamine in dairy products. Lower than 2.5 ppm (the safety limit in the USA and EU) of melamine in real samples can be detected exactly with the recoveries in a range from 98-115% using a 721-A spectrophotometer. More significantly, the existence of melamine can be visually evaluated easily without the aid of any instrumentation.

Recent advances in biological detection with magnetic nanoparticles as a useful tool

“…Ding et al [106] developed a simple and rapid colorimetric method for the determination of melamine in dairy products by Fe 3 O 4 MNPs-H 2 O 2 -ABTS detection system that does not require any expensive or complex instruments. The detection limit of melamine in real samples is lower than 2.5 ppm (the safety limit in the USA and EU) with the recoveries in a range from 98%-115%, using only a 721-A spectrophotometer without the aid of any instrumentation.…”

Label-free colorimetric sensor for mercury(II) and DNA on the basis of mercury(II) switched-on the oxidase-mimicking activity of silver nanoclusters

“…The challenge for colorimetric biosensing is transforming the detection signals into color changes which can be read by naked eyes. Nowadays, biosensors based on enzyme mimetics has emerged as a significant colorimetric tool for the detection of a variety of biomolecules, such as nucleotides [4], hydrogen peroxide (H 2 O 2 ) [5,6], glucose [7,8], melamine [9], xanthine [10] and so on. Enzyme mimetics are a hot research area at present because they can overcome some intrinsic drawbacks of natural enzymes.…”

Absorbance enhancement in microplate wells for improved-sensitivity biosensors

“…ssDNA (Mao et al, 2009;Sato et al, 2003), adenosine (Liu et al, 2006)) factors that control this mechanism. On the other side, some metal oxide NPs such as iron oxide (Fe 3 O 4 ) have been shown to exhibit an intrinsic mimetic peroxidase activity (Gao et al, 2007) which enabled their use as detection labels in ELISA or in H 2 O 2 -based melamine sensors (Ding et al, 2010). In order to improve the analytical performances of colorimetric detection systems the main effort has been focused at the reaction/recognition level by seeking catalysts with higher reaction rates and recognition biomolecules with higher affinity constants.…”