An "on-off-on" fluorescent probe for ascorbic acid based on Cu-ZnCdS quantum dots and α-MnO2 nanorods

作者:Rao, Hanbing; Gao, Yao; Ge, Hongwei; Zhang, Zhaoyi; Liu, Xin; Yang, Yan; Liu, Yaqin; Liu, Wei; Zou, Ping; Wang, Yanying*; Wang, Xianxiang; He, Hua; Zeng, Xianying
来源:Analytical and Bioanalytical Chemistry, 2017, 409(19): 4517-4528.
DOI:10.1007/s00216-017-0389-4

摘要

This work established a fluorescence approach for detecting ascorbic acid (AA) based on Cu-ZnCdS quantum dots (Cu-ZnCdS QDs) and alpha-MnO2 nanorods. Cu-ZnCdS QDs and alpha-MnO2 nanorods were characterized by high-resolution transmission electron microscopy (HRTEM), fluorescence spectroscopy, inductively coupled plasma optical emission spectroscopy (ICP-OES) and X-ray diffraction (XRD). In the presence of alpha-MnO2 nanorods, the fluorescence of Cu-ZnCdS QDs was greatly quenched through the inner filter effect (IFE). Subsequently, AA can trigger the decomposition of the alpha-MnO2 nanorods which can reduce alpha-MnO2 to Mn2+ and recover the fluorescence. Under optimal conditions, a linear relation was obtained over the range 5.02-401.77 mu M with a 31.62 mu M detection limit. Through applying the fluorescent sensing system for detecting AA, a satisfactory result is obtained with recoveries ranging from 89.23% to 110.99%.