Electroactive crown ester-Cu2+complex with in-situ modification at molecular beacon probe serving as a facile electrochemical DNA biosensor for the detection of CaMV 35s.
A novel electrochemical DNA biosensor has been facilely constructed by in-situ assembly of electroactive 4'-aminobenzo-18-crown-6-copper(II) complex (AbC-Cu2+) on the free terminal of the hairpin-structured molecule beacon. The 3'-SH modified molecule beacon probe was first immobilized on the gold electrode (AuE) surface through self-assembly chemistry of Au-S bond. Then the crow ester of AbC was covalently coupled with 5'-COOH on the molecule beacon, and served as a platform to attach the Cu2+by coordination with ether bond (-O-) of the crown cycle. Thus, an electroactive molecule beacon-based biosensing interface was constructed. In comparison with conventional methods for preparation of electroactive molecule beacon, the approach presented in this work is much simpler, reagent- and labor-saving. Selectivity study shows that the in-situ fabricated electroactive molecule beacon remains excellent recognition ability of pristine molecule beacon probe to well differentiate various DNA fragments. The target DNA can be quantatively determined over the range from 0.10pM to 0.50nM. The detection limit of 0.060pM was estimated based on signal-to-noise ratio of 3. When the biosensor was applied for the detection cauliflower mosaic virus 35s (CaMV 35s) in soybean extraction samples, satisfactory results are achieved. This work opens a new strategy for facilely fabricating electrochemical sensing interface, which also shows great potential in aptasensor and immurosensor fabrication.
College of Chemistry and Environment, Fujian Province Key Laboratory of Morden Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou 363000, PR China.
Fengping
F
Zhan
College of Chemistry and Environment, Fujian Province Key Laboratory of Morden Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou 363000, PR China.
Xiaolei
X
Liao
College of Chemistry and Environment, Fujian Province Key Laboratory of Morden Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou 363000, PR China.
Feng
F
Gao
College of Chemistry and Environment, Fujian Province Key Laboratory of Morden Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou 363000, PR China.
Weiwei
W
Qiu
College of Chemistry and Environment, Fujian Province Key Laboratory of Morden Analytical Science and Separation Technology, Minnan Normal University, Zhangzhou 363000, PR China. Electronic address: axiang236@126.com.
Qingxiang
Q
Wang
D015374:Biosensing Techniques / Q000379:methods*; D017796:Caulimovirus / Q000302:isolation & purification*; D056831:Coordination Complexes / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D043844:Crown Ethers / Q000737:chemistry*; D004279:DNA, Viral / Q000032:analysis*; D055664:Electrochemical Techniques / Q000379:methods; D004566:Electrodes; D006046:Gold / Q000737:chemistry; D057230:Limit of Detection; D009693:Nucleic Acid Hybridization / Q000379:methods; D010935:Plant Diseases / Q000821:virology*; D059629:Signal-To-Noise Ratio; D013025:Glycine max / Q000821:virology
D056831:Coordination Complexes; D043844:Crown Ethers; D004279:DNA, Viral; C015762:18-crown-6; D006046:Gold; D003300:Copper
4′-aminobenzo-18-crown-6; Copper complex; Electrochemical DNA sensor; In-situ modification; Molecule beacon