Premium
Reversing current rectification to improve DNA‐sensing sensitivity in conical nanopores
Author(s) -
Cai XiuHong,
Cao ShuoHui,
Cai ShengLin,
Wu YuanYi,
Ajmal Muhammad,
Li YaoQun
Publication year - 2019
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.201900002
Subject(s) - nanopore , rectification , conical surface , ion current , biosensor , materials science , current (fluid) , nanotechnology , ion , dna , cleavage (geology) , optoelectronics , analytical chemistry (journal) , chemistry , chemical physics , chromatography , physics , voltage , biochemistry , organic chemistry , quantum mechanics , fracture (geology) , composite material , thermodynamics
Herein, we report the ultrasensitive DNA detection through designing an elegant nanopore biosensor as the first case to realize the reversal of current rectification direction for sensing. Attributed to the unique asymmetric structure, the glass conical nanopore exhibits the sensitive response to the surface charge, which can be facilely monitored by ion current rectification curves. In our design, an enzymatic cleavage reaction was employed to alter the surface charge of the nanopore for DNA sensing. The measured ion current rectification was strongly responsive to DNA concentrations, even reaching to the reversed status from the negative ratio (−6.5) to the positive ratio (+16.1). The detectable concentration for DNA was as low as 0.1 fM. This is an ultrasensitive and label‐free DNA sensing approach, based on the rectification direction‐reversed amplification in a single glass conical nanopore.