Single glass nanopore-based regenerable sensing platforms with a non-immobilized polyglutamic acid probe for selective detection of cupric ions.
A single glass capillary nanopore-based sensing platform for rapid and selective detection of cupric ions is demonstrated by utilizing polyglutamic acid (PGA) as a non-immobilized probe. The detection is based on the significant decrease of ionic current through nanopore and the reversal of ion current rectification responses induced by the chelated cupric ions on the probes when in the presence of cupric ions. PGA shows high selectivity for detecting cupric ions rather than other metal ions. The sensitivity of the sensing platform can be improved about 1-2 orders of magnitude by employing asymmetric salt gradients during the measurements. And the PGA-based nanopore sensing platform shows excellent regenerability for Cu(2+) sensing applications. In addition, the method is found effective and reliable for the detection of cupric ions in real samples with small volume down to 20 μL. This nanopore-based sensing platform will find promising practical applications for the detection of cupric ions.
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Lizhen
L
Chen
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Haili
H
He
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, PR China.
Xiaolong
X
Xu
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, PR China. Electronic address: ydjin@ciac.ac.cn.
Yongdong
Y
Jin
D003300:Copper / Q000032:analysis*; D055664:Electrochemical Techniques; D004566:Electrodes; D005898:Glass / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007477:Ions / Q000737:chemistry; D015335:Molecular Probes / Q000737:chemistry; D058608:Nanopores; D011099:Polyglutamic Acid / Q000737:chemistry*; D015203:Reproducibility of Results
D007477:Ions; D015335:Molecular Probes; D011099:Polyglutamic Acid; D003300:Copper
Asymmetric salt gradients; Cupric ions; Nanopore; Polyglutamic acid; Regenerability; Selectivity