Ratiometric fluorescence probe of MIPs@CdTe QDs for trace malachite green detection in fish
A facile and practical ratiometric fluorescence probe based on two CdTe quantum dots (QDs) coated with molecularly imprinted polymers (MIPs) was prepared for the detection of trace malachite green (MG) in fish. Two CdTe QDs coated with MIPs were fabricated by a one-pot method using MG, (3-aminopropyl) triethoxysilane (APTES) and tetraethyl orthosilicate (TEOS) as template, functional monomer, and cross-linker, respectively. CdTe QDs with λem 530 nm (gQDs) and 630 nm (rQDs) were used as the referential fluorophore and target sensitive fluorophore, respectively. The fluorescence intensity of gQDs remained unchanged in the presence of MG, while the fluorescence of rQDs could be quantitatively quenched by MG based on the strategy of fluorescence resonance energy transfer. The ratiometric fluorescence probe (MIPs@gQDs&rQDs) was characterized by transmission electron microscopy and Fourier transform infrared spectroscopy. The linear range of MG detection was 0.1–32 μmol L−1 with a detection limit of 8.8 μg kg−1. The constructed probe has been successfully applied to the detection of MG in fish with the recoveries of 92.3–109.1%, which were validated by the method of HPLC. The result indicated that the probe possessed rapid response, wide linear range, high sensitivity, and relatively high selectivity, and was low-cost and easy in operation in the detection of MG in fish samples.
KeywordsCdTe quantum dots Ratiometric fluorescence probe Molecular imprinting polymer Malachite green Fish
This research was supported by the Foundation from the Science and Technology Planning Project of Fujian Province, China (2016Y0064), the Natural Science Foundation of Fujian Province of China (2018J01432, 2017J01633, 2017J01633), the Science and Technology Planning Project of Xiamen, China (3502Z20183031), Innovative Research Team of Jimei University, China (2010A007), and the National Undergraduate Training Programs for Innovation and Entrepreneurship, China (201610390042, 201710390022, 201810390071).
Compliance with ethical standards
The authors declare that they have no conflict of interest. This article does not contain any studies with human participants performed by any of the authors.
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