Nanopipette-DNA-Nanopore Hybrid System for Small Molecule Detection.

Area of Science:

• Nanotechnology
• Biosensing
• Molecular Biology

Background:

• Hybrid nanopores combine solid-state and DNA origami structures for molecular selectivity.
• Previous hybrid nanopore applications focused on macromolecules, not small molecules.
• Understanding DNA origami behavior in nanopores under high voltage is crucial.

Purpose of the Study:

• To develop and characterize a hybrid nanopore sensor for small-molecule detection.
• To investigate the specific binding and dissociation of adenosine triphosphate (ATP) using a DNA origami aptasensor.
• To demonstrate the feasibility of using hybrid nanopores for sensitive and selective small-molecule sensing.

Main Methods:

• Constructed a hybrid nanopore by trapping an ATP aptamer-modified DNA origami nanopore onto a nanopipette.
• Utilized electrophoretic trapping for nanopore assembly.
• Performed ion current measurements to analyze signal changes upon ATP binding and dissociation.

Main Results:

• Observed four distinct ion current signal types in the presence and absence of ATP.
• Demonstrated that the ratio of open/close signals increased threefold with ATP presence.
• Showed specific ATP detection, distinguishing it from ATP analogs like cytidine triphosphate.

Conclusions:

• Developed a versatile hybrid nanopore sensor capable of specific small-molecule detection.
• Provided fundamental insights into the behavior of DNA origami nanoplates in nanopores.
• Paved the way for advanced hybrid nanopore sensors in molecular diagnostics and analysis.