A novel sensitive colorimetric sensor for Cu2+based on in situ formation of fluorescent quantum dots with photocatalytic activity.
This work demonstrates the use of quantum dots (QDs) with photocatalytic activity as a sensitive, inexpensive and rapid colorimetric platform for Cu2+sensing. Based on the simple thiol compound mediated QDs growing method, CdS QDs can be quickly formed in situ, which possess excellent photocatalytic ability for the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to produce a colored product under light irradiation. Cu2+can catalyze the oxidation of sulfhydryl groups in glutathione (GSH) which act as a stabilizer for CdS QDs. In the presence of Cu2+, GSH is oxidized and loss the stabilization ability for the growth of CdS QDs, thus resulting in the decrease of the absorbance. Under optimum conditions, as low as 5.3nM Cu2+can be detected. This sensing system is simple, reliable and holds great potential to provide a new general platform for ultrasensitive monitoring of a variety of analytes.
Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350108, China. Electronic address: srtang@fjmu.edu.cn.
Shurong
S
Tang
Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, Testing Center, Fuzhou University, Fuzhou, Fujian 350108, China.
Meili
M
Wang
Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350108, China.
Zhijun
Z
Li
Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, Testing Center, Fuzhou University, Fuzhou, Fujian 350108, China.
Ping
P
Tong
Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, Testing Center, Fuzhou University, Fuzhou, Fujian 350108, China.
Qiang
Q
Chen
Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350108, China.
Guangwen
G
Li
Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350108, China.
Jinghua
J
Chen
Ministry of Education Key Laboratory of Analysis and Detection for Food Safety, Testing Center, Fuzhou University, Fuzhou, Fujian 350108, China. Electronic address: zlan@fzu.edu.cn.
Lan
L
Zhang
D015374:Biosensing Techniques; D003124:Colorimetry; D003300:Copper / Q000737:chemistry / Q000302:isolation & purification*; D005978:Glutathione / Q000737:chemistry*; D008027:Light; D045663:Quantum Dots / Q000737:chemistry
D003300:Copper; D005978:Glutathione
Colorimetric sensor; Copper ions; Photocatalytic activity; Quantum dots