Insulated gold scanning tunneling microscopy probes for recognition tunneling in an aqueous environment

Tuchband, Michael R.; He, Jin; Huang, Shuo; Lindsay, Stuart

doi:10.1063/1.3673640

Cited by 30 publications

(38 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Finally, for the few devices with which we observed DNA translocations and that did not rupture before taking a nanoelectrode measurement, the nanoelectrode signal was not reliable. We observed cases where the signal fluctuated wildly, where the nanoelectrode current increased steadily with time, or where the current increased steadily to a plateau that was much larger than could be expected for the exposed area of gold at the electrode tips . We also saw cases where the current was steady at similarly large current for the duration of the measurement.…”

Section: Resultsmentioning

confidence: 66%

Fabrication and characterization of nanopores with insulated transverse nanoelectrodes for DNA sensing in salt solution

et al. 2012

View full text Add to dashboard Cite

We report on the fabrication, simulation, and characterization of insulated nanoelectrodes aligned with nanopores in low-capacitance silicon nitride membrane chips. We are exploring these devices for the transverse sensing of DNA molecules as they are electrophoretically driven through the nanopore in a linear fashion. While we are currently working with relatively large nanopores (6–12 nm in diameter) to demonstrate the transverse detection of DNA, our ultimate goal is to reduce the size sufficiently to resolve individual nucleotide bases, thus sequencing DNA as it passes through the pore. We present simulations and experiments that study the impact of insulating these electrodes, which is important to localize the sensing region. We test whether the presence of nanoelectrodes or insulation affects the stability of the ionic current flowing through the nanopore, or the characteristics of DNA translocation. Finally, we summarize the common device failures and challenges encountered during fabrication and experiments, explore the causes of these failures, and make suggestions on how to overcome them in the future.

show abstract

Section: Resultsmentioning

confidence: 66%

Fabrication and characterization of nanopores with insulated transverse nanoelectrodes for DNA sensing in salt solution

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Our yield of functionalized probes is now quite high 16 and is characterized by comparing the signals generated in a tunnel junction to the control signals described here. Since junctions lacking the adaptor molecule on one electrode give a characteristic signal that is different from that obtained when both electrodes are functionalized, we are able to test whether or not we have successfully functionalized probes.…”

Section: 0 Results and Discussionmentioning

confidence: 99%

Chemical recognition and binding kinetics in a functionalized tunnel junction

et al. 2012

Self Cite

View full text Add to dashboard Cite

4(5)-(2-mercaptoethyl)-1H-imidazole-2-carboxamide is a molecule that has multiple hydrogen bonding sites and a short flexible linker. When tethered to a pair of electrodes, it traps target molecules in a tunnel junction. Surprisingly large recognition-tunneling signals are generated for all naturally occurring DNA bases A, C, G,T, and 5-methyl-Cytosine. Tunnel current spikes are stochastic and broadly distributed, but characteristic enough so that individual bases can be identified as a tunneling probe is scanned over DNA oligomers. Each base yields a recognizable burst of signal, the duration of which is controlled entirely by the probe speed, down to speeds of 1 nm/s, implying a maximum off-rate of 3 s-1 for the recognition complex. The same measurements yield a lower bound on the on-rate of ~1 M-1s-1. Despite the stochastic nature of the signals, an optimized multi-parameter fit allows base-calling from a single signal peak with an accuracy that can exceed 80% when a single type of nucleotide is present in the junction, meaning that recognition-tunneling is capable of true single-molecule analysis. The accuracy increases to 95% when multiple spikes in a signal cluster are analyzed.

show abstract

“…Chemical Modification of the GNE : The details of electrochemical etching, insulation, and characterization of GNE are found in Supporting Information and elsewhere . The quality of SAM was critical to achieve reproducible signal.…”

Section: Methodsmentioning

confidence: 99%

Monitoring the Dynamic Process of Formation of Plasmonic Molecular Junctions during Single Nanoparticle Collisions

Guo

Chang

Wang

et al. 2018

Small

Self Cite

View full text Add to dashboard Cite

The capability to study the dynamic formation of plasmonic molecular junction is of fundamental importance, and it will provide new insights into molecular electronics/plasmonics, single-entity electrochemistry, and nanooptoelectronics. Here, a facile method to form plasmonic molecular junctions is reported by utilizing single gold nanoparticle (NP) collision events at a highly curved gold nanoelectrode modified with a self-assembled monolayer. By using time-resolved electrochemical current measurement and surface-enhanced Raman scattering spectroscopy, the current changes and the evolution of interfacial chemical bonding are successfully observed in the newly formed molecular tunnel junctions during and after the gold NP "hit-n-stay" and "hit-n-run" collision events. The results lead to an in-depth understanding of the single NP motion and the associated molecular level changes during the formation of the plasmonic molecular junctions in a single NP collision event. This method also provides a new platform to study molecular changes at the single molecule level during electron transport in a dynamic molecular tunnel junction.

show abstract

Insulated gold scanning tunneling microscopy probes for recognition tunneling in an aqueous environment

Cited by 30 publications

References 20 publications

Fabrication and characterization of nanopores with insulated transverse nanoelectrodes for DNA sensing in salt solution

Fabrication and characterization of nanopores with insulated transverse nanoelectrodes for DNA sensing in salt solution

Chemical recognition and binding kinetics in a functionalized tunnel junction

Monitoring the Dynamic Process of Formation of Plasmonic Molecular Junctions during Single Nanoparticle Collisions

Contact Info

Product

Resources

About