文獻名： A double signal optical probe composed of carbon quantum dots and Au@ Ag nanoparticles grown in situ for the high sensitivity detection of ellagic acid

 

 

作者： Xiu Qin, Chunling Yuan, Rui Shi, Yilin Wang

School of Chemistry and Chemical Engineering, Guangxi Key Laboratory of Biorefinery, Guangxi

University, Nanning 530004, China

 

 

摘要：Carbon quantum dots (CQDs) were prepared from trifolium leaves via hydrothermal method, a fluorometric and colorimetric double signal probe based on CQDs-gold nanoparticles (AuNPs)-AgNO₃ system was constructed for the detection of ellagic acid (EA). In this system, Ag⁺ ions were reduced by EA to Ag atoms, which deposited on the surfaces of AuNPs to form Au@AgNPs in situ, along with an obvious color change from pink to yellow. Simultaneously, the fluorescence of CQDs was quenched by Au@AgNPs, attributing to inner filter effect (IFE). Under the optimal conditions, sensitive assay of EA was achieved, with the limit of detection (LOD) of 0.41 μM for fluorescence analysis and 0.22 μM for colorimetric assay. The changes of fluorescence and absorbance correlated well with EA concentration in the range of 0.50–25.0 μM. In addition, the double signal probe also exhibited high selectivity toward EA. The feasibility of the probe was confirmed in commercial cosmetics analysis with satisfactory results.

 

關鍵詞：Gold nanoparticles;Determination;Fluorescence;Colorimetry