Practical and regenerable electrochemical aptasensor based on nanoporous gold and thymine-Hg2+-thymine base pairs for Hg2+detection.
A simple, practical and reusable electrochemical aptasensor, based on thymine-Hg2+-thymine (T-Hg2+-T) coordination chemistry and nanoporous gold (NPG) for signal amplification, was designed for sensitive and selective detection of mercury ions (Hg2+). The thiol modified T-rich hairpin capture probe was self-assembled onto the surface of the NPG modified electrode for hybridizing with ferrocene-labeled T-rich probe in the presence of Hg2+via T-Hg2+-T coordination chemistry. As a result, the hairpin capture probe was opened, and the ferrocene tags were close to the NPG modified electrode. Taking advantage of the amplification effect of NPG electrode for increasing the reaction sites of thiol modified capture probe, the proposed electrochemical aptasensor could detect Hg2+quantitatively in the range of 0.01-5000nM, with a detection limit as low as 0.0036nM which is much lower than the maximum contamination level for Hg2+in drinking water defined by the U.S. Environmental Protection Agency. Moreover, the proposed electrochemical aptasensor can be regenerated by adding cysteine and Mg2+. The aptasensor was also used to detect Hg2+from real water samples, and the results showed excellent agreement with the values determined by atomic fluorescence spectrometer. This aptasensor showed a promising potential for on-site detecting Hg2+in drinking water.
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China. Electronic address: zgming@hnu.edu.cn.
Guangming
G
Zeng
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
Chen
C
Zhang
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China. Electronic address: huangdanlian@hnu.edu.cn.
Danlian
D
Huang
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
Cui
C
Lai
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
Lin
L
Tang
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China; College of Resources and Environment, Hunan Agricultural University, Changsha 410128, PR China.
Yaoyu
Y
Zhou
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
Piao
P
Xu
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
Hou
H
Wang
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
Lei
L
Qin
College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China; Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Ministry of Education, Changsha 410082, PR China.
Min
M
Cheng
D020029:Base Pairing; D015374:Biosensing Techniques; D060766:Drinking Water / Q000737:chemistry*; D055664:Electrochemical Techniques; D006046:Gold / Q000737:chemistry; D006801:Humans; D057230:Limit of Detection; D008628:Mercury / Q000737:chemistry / Q000302:isolation & purification*; D053768:Metal Nanoparticles / Q000737:chemistry; D013941:Thymine / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*
D060766:Drinking Water; D014874:Water Pollutants, Chemical; D006046:Gold; D008628:Mercury; D013941:Thymine
Amplification; Electrochemistry; Hg(2+); Nanoporous gold; Thymine-Hg(2+)-thymine