A label-free photoelectrochemical aptasensor based on nitrogen-doped graphene quantum dots for chloramphenicol determination.
A photoelectrochemical (PEC) sensing platform for chloramphenicol (CAP) detection was constructed using nitrogen-doped graphene quantum dots (N-GQDs) as transducer species and label-free aptamer as biological recognition element. N-GQDs, synthesized via a facile one-step hydrothermal method, were explored to achieve highly efficient photon-to-electricity conversion under visible light irradiation. The obtained N-GQDs were characterized by transmission electron microscopy (TEM), which displayed a narrow size distribution with a mean diameter of 2.14 nm. The X-ray photoelectron spectroscopic (XPS) and Fourier transform infrared spectroscopic (FT-IR) analysis confirmed that nitrogen was successfully doped in GQDs. The UV-visible absorption spectra indicated that nitrogen doping obviously enhanced the absorption of GQDs in visible light region. As a result, the PEC activity of GQDs was promoted by nitrogen doping. Additionally, the π-conjugated structure of N-GQDs provided an excellent platform for aptamer immobilization via π-π stacking interaction. Such an aptamer/N-GQDs based sensor showed a linear PEC response to CAP concentration in the range of 10-250 nM with a detection limit (3 S/N) of 3.1 nM. The developed PEC aptasensor exhibited high sensitivity and selectivity, good reproducibility and high stability.
Key Laboratory for Large-Format Battery Materials and System (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, PR China.
Yong
Y
Liu
Key Laboratory for Large-Format Battery Materials and System (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, PR China.
Kai
K
Yan
Key Laboratory for Large-Format Battery Materials and System (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, PR China.
Otieno Kevin
OK
Okoth
Key Laboratory for Large-Format Battery Materials and System (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, PR China. Electronic address: zhangjd@mail.hust.edu.cn.
Jingdong
J
Zhang
D000900:Anti-Bacterial Agents / Q000032:analysis; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D002701:Chloramphenicol / Q000032:analysis*; D003217:Conductometry / Q000295:instrumentation*; D004784:Environmental Monitoring / Q000295:instrumentation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry; D010783:Photometry / Q000295:instrumentation*; D045663:Quantum Dots; D014874:Water Pollutants, Chemical / Q000032:analysis*
D000900:Anti-Bacterial Agents; D052157:Aptamers, Nucleotide; D014874:Water Pollutants, Chemical; D002701:Chloramphenicol; D006108:Graphite; D009584:Nitrogen
Aptamer; Chloramphenicol; Nitrogen-doped graphene quantum dots; Photoelectrochemical sensor