Visual detection of melamine by using a ratiometric fluorescent probe consisting of a red emitting CdTe core and a green emitting CdTe shell coated with a molecularly imprinted polymer.
Mikrochim Acta
; 185(2): 135, 2018 01 26.
Article
em En
| MEDLINE
| ID: mdl-29594750
ABSTRACT
A composite ratiometric fluorescent probe is described for visual detection of melamine (MEL) in milk samples. It is based on the use of red emitting and green emitting CdTe quantum dots, and a mesoporous molecularly imprinted polymer. The red emitting QDs are embedded in the silica microsphere to serve as a core, and the green emitting QDs are coated on the surface of the silica microsphere as a shell. A molecularly imprinted polymer (MIP) with specific recognition sites for MEL was placed on the shell. If MEL is bound by the MIP, the green fluorescence is quenched due to hydrogen bond interaction. The red emission, in contrast, remains unchanged. Quenching leads to a change in the color of fluorescence from red-green to purely red. This effect allows for visual and instrumental detection of MEL. The mesoporous structure of the MIP reduces the mass transfer resistance and enhances the accessibility of sites for MEL. Response is linear in the 50-1000 ng mL-1 MEL concentration range, and the limit of detection is 13 ng mL-1. The fluorescent probe was successfully applied to the analysis of MEL-spiked milk samples and gave recoveries between 94.1 and 98.7%, with 3.6-5.1% relative standard deviations. Graphical abstract Schematic of the preparation and detection of the composite probe. The probe was applied for the selective recognition and visual detection of melamine (MEL).
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
Mikrochim Acta
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
China