A facile and green strategy for preparing newly-designed 3D graphene/gold film and its application in highly efficient electrochemical mercury assay.
In this work, we report a facile and green strategy for in situ and one step preparation of a novel 3D graphene/gold (G/Au) film. Triggering with unique driving force from hydrothermal growth, a 3D interlaced graphene framework with hierarchically porous structures was directly attached on a gold substrate pretreated with a self-assembled monolayer. Simultaneously, highly dispersive Au nanoparticles with tunable morphologies were anchored on the framework utilizing generated graphene as an endogenous reductant. Newly-designed 3D G/Au film possessed excellent properties of significantly large specific area, good electrical conductivity, high structure stability and substrate binding strength, etc. As a paradigm, an electrochemical Hg2+biosensor was constructed on 3D G/Au film, in which an exonuclease III-assisted target recycling was introduced. Impressively, an ultralow detection limit of 50 aM (S/N=3), a wide linear range from 0.1 fM to 0.1μM, a high selectivity and a good reliability for Hg2+assay in real water and serum samples were realized using prepared biosensor. It is highly envisioned that this work opens the door towards simply fabricating varying types of 3D graphene based hybrid films, and such G/Au film will have widespread applications in electroanalysis and electrocatalysis.
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China.
Lei
L
Shi
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China.
Yan
Y
Wang
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, PR China. Electronic address: smding@niglas.ac.cn.
Shiming
S
Ding
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, PR China.
Zhenyu
Z
Chu
School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, PR China.
Yu
Y
Yin
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, PR China.
Danfeng
D
Jiang
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, PR China.
Jingyi
J
Luo
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing 210009, PR China.
Wanqin
W
Jin
D015374:Biosensing Techniques; D055664:Electrochemical Techniques; D005090:Exodeoxyribonucleases / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D057230:Limit of Detection; D008628:Mercury / Q000737:chemistry / Q000302:isolation & purification*; D053768:Metal Nanoparticles / Q000737:chemistry
D006046:Gold; D006108:Graphite; D005090:Exodeoxyribonucleases; C020133:exodeoxyribonuclease III; D008628:Mercury
3D graphene/gold film; Hydrothermal growth; In situ preparation; Mercury sensing; Target recycling