An ionic liquid supported CeO2 nanoparticles-carbon nanotubes composite-enhanced electrochemical DNA-based sensor for the detection of Pb2+
10.1016/j.jpha.2011.09.001
- Author:
Yan LI
;
Xiaorong LIU
;
Xiaohui NING
;
Cancan HUANG
;
Jianbin ZHENG
;
Juncai ZHANG
- Publication Type:Journal Article
- Keywords:
Electrochemical;
DNA-based sensor;
Lead (Ⅱ) ion;
Ionic liquid;
CeO2 nanoparticle;
Multi-wall carbon nanotubes
- From:
Journal of Pharmaceutical Analysis
2011;01(4):258-263
- CountryChina
- Language:Chinese
-
Abstract:
An electrochemical sensor incorporating a signal enhancement for the determination of lead (Ⅱ) ions (Pb2+) was designed on the basis of the thrombin-binding aptamer (TBA) as a molecular recognition element and ionic liquid supported cerium oxide (CeO2) nanoparticles-carbon nanotubes composite modification. The composite comprises nanoparticles CeO2, multi-wall carbon nanotubes (MWNTs)and hydrophobic room temperature ionic liquid (RTIL) l-ethyl-3-methylimidazolium tetrafluoroborate (EM1MBF4). The electrochemical sensors were fabricated by immersing the CeO2-MWNTs-EMIMBF4 modified glassy carbon electrode (GCE) into the solution of TBA probe. In the presence of Pb2+, the TBA probe could form stable G-quartet structure by the specific binding interactions between Pb2+ and TBA. The TBA-bound Pb2+ can be electrochemically reduced, which provides a readout signal for quantitative detection of Pb2+. The reduction peak current is linearly related to the concentration of Pb2+ from 1.0 × 10 8 M to 1.0 × 10-5 M with a detection limit of 5 × 109 M. This work demonstrates that the CeO2-MWNTs-EMIMBF4 nanocomposite modified GCE provides a promising platform for immobilizing the TBA probe and enhancing the sensitivity of the DNA-based sensors.
