PMID- 26839920
OWN - NLM
STAT- MEDLINE
DCOM- 20170104
LR  - 20170105
IS  - 1364-5528 (Electronic)
IS  - 0003-2654 (Linking)
VI  - 141
IP  - 5
DP  - 2016 Mar 7
TI  - Exonuclease I-aided homogeneous electrochemical strategy for organophosphorus 
      pesticide detection based on enzyme inhibition integrated with a DNA 
      conformational switch.
PG  - 1830-6
LID - 10.1039/c5an02374b [doi]
AB  - A novel enzyme inhibition-based homogeneous electrochemical biosensing strategy 
      was designed for an organophosphorus pesticide assay based on exploiting the 
      resistance of a mercury ion-mediated helper probe (HP) toward nuclease-catalyzed 
      digestion and the remarkable diffusivity difference between HPs and the 
      mononucleotides toward a negatively charged indium tin oxide (ITO) electrode. In 
      particular, the mercury ion-mediated T-Hg(2+)-T base pairs facilitate the HP 
      labeled with methylene blue (MB) to fold into a hairpin structure, preventing its 
      digestion by exonuclease I, and thus resulting in a low electrochemical response 
      because of the large electrostatic repulsion between the negatively charged ITO 
      electrode and the HPs. The competitive binding by a thiol group (-SH), produced 
      in the hydrolysis reaction of acetylthiocholine (ACh) chloride with 
      acetylcholinesterase (AChE), removes mercury ions from the base pairs, causing a 
      nuclease-catalyzed digestion, and the subsequent electrochemical response 
      increase due to the weak electrostatic repulsion between the 
      product-mononucleotides and the ITO electrode. Mercury ion-mediated HPs were 
      first designed for pesticide detection and diazinon was chosen as the model 
      target. Under the optimal experimental conditions, the approach exhibited high 
      sensitivity for diazinon detection with a detection limit of 0.25 mug L(-1). The 
      satisfactory results in the determination of diazinon in real samples demonstrate 
      that the method possesses great potential for detecting organophosphorus 
      pesticides. This new approach is expected to promote the exploitation of 
      mercury-mediated base pair-based homogenous electrochemical biosensors in 
      biochemical studies and in the food safety field.
FAU - Wang, Xiuzhong
AU  - Wang X
AD  - College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural 
      University, Qingdao 266109, China. lifeng@qust.edu.cn.
FAU - Dong, Shanshan
AU  - Dong S
AD  - College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural 
      University, Qingdao 266109, China. lifeng@qust.edu.cn.
FAU - Hou, Ting
AU  - Hou T
AD  - College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural 
      University, Qingdao 266109, China. lifeng@qust.edu.cn.
FAU - Liu, Lei
AU  - Liu L
AD  - College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural 
      University, Qingdao 266109, China. lifeng@qust.edu.cn.
FAU - Liu, Xiaojuan
AU  - Liu X
AD  - College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural 
      University, Qingdao 266109, China. lifeng@qust.edu.cn.
FAU - Li, Feng
AU  - Li F
AD  - College of Chemistry and Pharmaceutical Sciences, Qingdao Agricultural 
      University, Qingdao 266109, China. lifeng@qust.edu.cn.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - Analyst
JT  - The Analyst
JID - 0372652
RN  - 0 (Enzyme Inhibitors)
RN  - 0 (Organophosphorus Compounds)
RN  - 0 (Pesticide Residues)
RN  - 0 (Pesticides)
RN  - 059QF0KO0R (Water)
RN  - 9007-49-2 (DNA)
RN  - EC 3.1.- (Exodeoxyribonucleases)
RN  - EC 3.1.11.1 (exodeoxyribonuclease I)
SB  - IM
MH  - Animals
MH  - *Biocatalysis
MH  - Biosensing Techniques/instrumentation/*methods
MH  - DNA/*chemistry
MH  - Electrochemistry
MH  - Electrophorus
MH  - Enzyme Inhibitors/analysis/pharmacology
MH  - Equipment Design
MH  - Exodeoxyribonucleases/*antagonists & inhibitors/*metabolism
MH  - Feasibility Studies
MH  - Food Safety
MH  - Limit of Detection
MH  - *Nucleic Acid Conformation
MH  - Organophosphorus Compounds/*analysis/pharmacology
MH  - Pesticide Residues/analysis/pharmacology
MH  - Pesticides/analysis/pharmacology
MH  - Water/chemistry
EDAT- 2016/02/04 06:00
MHDA- 2017/01/05 06:00
CRDT- 2016/02/04 06:00
PHST- 2016/02/04 06:00 [entrez]
PHST- 2016/02/04 06:00 [pubmed]
PHST- 2017/01/05 06:00 [medline]
AID - 10.1039/c5an02374b [doi]
PST - ppublish
SO  - Analyst. 2016 Mar 7;141(5):1830-6. doi: 10.1039/c5an02374b.