Tunable DNA Origami Nanosensors for Detection of Multiscale Spatial Ion Concentration Gradients

Area of Science:

• Biotechnology
• Nanotechnology
• Biochemistry

Background:

• Ion gradients are crucial for cellular signaling, mechanobiology, and homeostasis.
• Conventional fluorescent sensors lack the tunability and spatial resolution needed for accurate mapping of ion gradients at biologically relevant scales.

Purpose of the Study:

• To develop a DNA origami-based sensor (NanoDyn) with tunable sensitivity for detecting sodium (Na+) ion gradients.
• To enable the mapping of ion gradients across micron to millimeter scales with high spatial resolution.

Main Methods:

• Utilized programmable DNA base-pairing interactions for sensor design.
• Employed fluorescence spectroscopy to characterize sensor performance.
• Used a custom microfluidic gradient generator to validate spatial resolution and gradient quantification.

Main Results:

• NanoDyn demonstrated programmable sensing ranges from approximately 100 to 1675 mM Na+.
• The sensor resolved ion gradient changes over distances as small as ~6 μm, limited by the microfluidic device resolution.
• Validated the sensor's ability to quantify ion gradients across multiple scales.

Conclusions:

• NanoDyn advances DNA nanotechnology for multiscale, tunable ion gradient sensing.
• The sensor offers biocompatibility, high temporal resolution, and potential for multiplexed functionalization.
• This work expands the application of DNA nanodevices in spatial sensing for ion-mediated processes in microenvironments and disease research.