Assembly-Induced Emission Enhancement in Glutathione-Capped Bimetallic Gold and Copper Nanoclusters by Al3+ Ions and Further Application in Myricetin Determination

Abstract

A significant emission enhancement (>100-fold) of glutathione-capped bimetallic gold and copper nanoclusters (AuCuNC@GSH) was achieved by assembling with Al3+ ions and by assembly-induced emission enhancement (AIEE). Further chelation of myricetin to Al3+ resulted in emission quenching of AuCuNC-Al3+, which was applied to specifically detect myricetin. Two linear responses were shown in the range of 0–1.5 μM and 1.5–50 μM, separately, leading to a low limit of detection at 8.7 nM. The method was successfully and accurately applied to myricetin determination in grape juice, which showed good application for real samples. Finally, the in-depth mechanism revealed that both the chelation of myricetin and Al3+ and the inner filter effect (IFE) between myricetin-Al3+ and AuCuNC-Al3+ greatly contributed to the quenching response of myricetin. Therefore, the present study provides an easy way to improve the fluorescence property of metal nanoclusters. Additionally, it supplies a cost-effective and easily performed approach to detect myricetin with high selectivity and sensitivity.

Recent Advances in Gold Nanocluster-Based Biosensing and Therapy: A Review

“…In comparison to ions, small molecules are larger in size and difficult to approach at the Au NC surface because of the steric hindrance effect. For the detection of small molecules, there are three major pathways [42][43][44][45][46][47][48][49][50]. 1.…”