Date:

2025-04-30

Title of Paper:

Dual-mode melamine detection based on gold nanoparticlesaggregation-induced fluorescence “turn-on” and “turn-off” of CdTequantum dots

Journal:

Sensors and Actuators B

Summary:

Both “turn-on” and “turn-off” fluorescent probe for the determination of melamine have been developedby tuning the inner filter effect (IFE) from CdTe quantum dots (QDs) to gold nanoparticles. Because ofthe melamine-induced aggregation of gold nanoparticles, the first absorption peak of the transversesurface plasmon resonance (SPR) at 520 nm fades down, whereas the second absorption peak of thelongitudinal SPR around 620 nm gets intense. The decrease of the transverse SPR reduces the IFE ofthe bundled CdTe QDs with an emission band at 525 nm (the corresponding particle size is 1.98 nm),which results in the melamine concentration-dependent fluorescence recovery of CdTe QDs. The increaseof the longitudinal SPR enhances the IFE of the bundled CdTe QDs with an emission band at 620 nm(the corresponding particle size is 3.68 nm), which results in the melamine concentration-dependentfluorescence decrease of CdTe QDs. The green mode detection with the fluorescence recovery has a linearresponse for melamine from 20 to 100 ng/mL with a theoretical detection limit of 8 ng/mL. The red modedetection with the fluorescence decrease has a linear response for melamine from 20 to 100 ng/mL witha theoretical detection limit of 11 ng/mL. Interference studies and real samples detection show that themelamine could be specifically detected using this dual-mode fluorescent probe.. 2016 Elsevier B.V. All rights reserved.

Co-author:

Jian Zhu∗, Hui Chang, Jian-Jun Li, Xin Li, Jun-Wu Zhao∗

Translation or Not:

No

Date of Publication:

2017-01-01