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Updated: Dec 2, 2025

Compact Quantum Dots for Single-molecule Imaging
Published on: October 9, 2012
A glycine-functionalized graphene quantum dots synthesized by a facile post-modification strategy for a sensitive and
Qianqian Zhu1, Haichen Mao1, Jianjun Li1
1College of Chemistry, Green Catalysis Center, Henan Joint International Research Laboratory of Green Construction of Functional Molecules and Their Bioanalytical Applications, Zhengzhou University, Zhengzhou 450001, China.
Abstract:
In this work, we have developed a facile method for the synthesis of glycine-functionalized graphene quantum dots (Gly-GQDs) through post-modification of graphene quantum dots with Gly under alkaline conditions. The as-synthesized Gly-GQDs exhibit an excellent blue emission at 444 nm, independent of excitation, as well as a high quantum yield (QY) of 35.7%. The Gly-GQDs have a narrow size distribution with an average size of 5.9 nm. Moreover, the as-prepared Gly-GQDs showed a better selective and sensitive recognition capability towards mercury ion (Hg2+) in aqueous solutions with a low detection limit of 8.3 nM, compared with GQDs and other nitrogen-doped GQDs synthesized through the one-step solvent thermal method. Gly-GQDs are successfully applied for the determination of Hg2+ in real water samples. This work shows a new promising approach for the design and synthesis of desirable GQDs with a given function.

