Gate effects on DNA translocation through silicon dioxide nanopore

Area of Science:

• Nanotechnology
• Molecular Biology
• Biophysics

Background:

• Nanopore sequencing is a rapidly developing technology for DNA analysis.
• Controlling molecule dynamics within nanopores is crucial for improving resolution and accuracy.
• Understanding the influence of electrical fields on translocation is key for nanopore device optimization.

Purpose of the Study:

• To investigate the impact of applied gate voltage on DNA molecule translocation dynamics through a nanopore.
• To quantify changes in translocation time, ionic current, and blockage amplitude under varying gate voltages.
• To analyze the modulation of event frequency and dwell time distributions.

Main Methods:

• Utilizing a nanopore setup to monitor ionic current changes during DNA molecule passage.
• Applying a positive gate voltage to the system to observe its effects on translocation.
• Analyzing current blockage events, translocation times, and dwell time distributions.
• Comparing experimental observations with theoretical models.

Main Results:

• A twenty-fold increase in DNA translocation time was observed with a positive gate voltage.
• Ionic current remained largely unchanged, while current blockage amplitude decreased proportionally to translocation time.
• The frequency of blocking events significantly decreased under applied gate voltage.
• The scatter plot of current blockage amplitude versus dwell time showed modulation by the gate voltage.

Conclusions:

• Applied gate voltage significantly alters DNA translocation dynamics in nanopores.
• The observed effects, including increased translocation time and reduced blockage, are consistent with theoretical predictions.
• Gate voltage offers a viable method for controlling and optimizing DNA translocation in nanopore devices.