Resistive-pulse detection of short dsDNAs using a chemically functionalized conical nanopore sensor.
OBJECTIVE
To develop nanopore resistive-pulse sensors for the detection of short (50 base-pair [bp] and 100 bp) DNAs.


METHODS
Conically shaped nanopores were chemical etched into polyethylene terphthalate membranes. The as-etched membrane had anionic carboxylate sites on the pore walls. Neutral and hydrophilic ethanolamine functional groups were attached to these carboxylate sites using well-established EDC (1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride) chemistry.


CONCLUSIONS
The ethanolamine-functionalized pores were used to detect 50 and 100 bp DNAs via the resistive-pulse method. The resistive-pulse signature produced by the 50 bp DNA could be distinguished from that of the 100 bp DNA with these sensors.


CONCLUSIONS
Attachment of ethanolamine to the carboxylate groups on the pore wall lowered the anionic charge density on the wall. This mitigated the problem of electrostatic rejection of the anionic DNAs from the pore and enabled the detection of these DNA analytes.
Kececi
Kaan
K
Department of Chemistry, Center for Research at the Bio/Nano Interface, University of Florida, Gainesville, FL 32611-7200, USA.
Sexton
Lindsay T
LT
Buyukserin
Fatih
F
Martin
Charles R
CR
D015374:Biosensing Techniques; D002264:Carboxylic Acids / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry; D004563:Electrochemistry / Q000379:methods; D029968:Escherichia coli Proteins / Q000737:chemistry; D004983:Ethanolamines / Q000737:chemistry; D006460:Hemolysin Proteins / Q000737:chemistry; D008567:Membranes, Artificial; D053758:Nanoparticles / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D043942:Nanotubes / Q000737:chemistry; D010316:Particle Size; D013052:Spectrometry, X-Ray Emission; D055672:Static Electricity; D013499:Surface Properties
D002264:Carboxylic Acids; D004277:DNA, Single-Stranded; D029968:Escherichia coli Proteins; D004983:Ethanolamines; D006460:Hemolysin Proteins; C036507:Hlya protein, E coli; D008567:Membranes, Artificial; D004247:DNA