Nanofluidic Transport Phenomena and Applications

Nanofluidics addresses the behaviour of liquids and dissolved species in conduits with characteristic dimensions below 100 nm. Under such extreme confinement, classical hydrodynamic and electrostatic models merge with molecular‐scale effects, giving rise to phenomena including overlapping electric double layers, surface‐charge-governed ion selectivity and enhanced electro-osmotic flows. These effects underpin applications from energy harvesting—where salinity gradients across charged nanochannels yield osmotic power—to ultrasensitive biosensing, in which individual biomolecules are driven through nanopores for high-resolution detection. Advances in materials design, surface functionalisation and nanofabrication have enabled a new generation of devices capable of active ion pumping, precise molecular discrimination and robust operation under harsh chemical or thermal conditions. The global significance of such developments spans sustainable power generation, next-generation sequencing, water desalination and integrated lab-on-chip diagnostics.

Research from Nature Portfolio

Recent studies have shown that engineered charge-selective nanopores can capture, unfold and translocate full-length polypeptides without enzymes, using electro-osmotic flow to locate post-translational modifications deep within protein chains. This approach lays the groundwork for comprehensive proteoform inventories at the single-molecule level. In parallel, composite membranes combining two-dimensional MXene sheets with Kevlar nanofibres exploit synergistic surface and space charges to achieve power densities exceeding 4 W m⁻² under realistic seawater–river water gradients, guided by joint experimental and theoretical insights into confined ion diffusion. Furthermore, light-driven active transport has been demonstrated in layered graphene oxide membranes: asymmetric illumination induces photon–electron–ion coupling, enabling uphill cation pumping and the development of photonic ion diodes and transistors as elementary components for synthetic nanofluidic circuitry.

Nanofluidic Transport Phenomena and Applications publication trend

The graph below shows the total number of articles in nanofluidic transport phenomena and applications across all publications each year (not limited to Nature Index journals).

Technical terms

Electric double layer (EDL): the region of charge accumulation at a solid–fluid interface influencing ion distribution under confinement.

Electro-osmosis: fluid motion induced by an applied electric field acting on the EDL, used to drive fluids and molecules through nanoscale channels.

Nanopore: a nanoscale aperture in a thin membrane that permits single-molecule transport and ionic current detection for sequencing or sensing.

Osmotic energy conversion: generation of electrical power from a salinity difference across ion-selective nanochannels or membranes.

Photonic ion transport: active ion movement driven by light-induced charge separation in photoresponsive nanofluidic materials.

References

1. Anti-Swelling Polyelectrolyte Hydrogel with Submillimeter Lateral Confinement for Osmotic Energy Conversion. Nano-Micro Letters (2024).
2. Enzyme-less nanopore detection of post-translational modifications within long polypeptides. Nature Nanotechnology (2023).
3. Mechanically strong MXene/Kevlar nanofiber composite membranes as high-performance nanofluidic osmotic power generators. Nature Communications (2019).
4. Nanopore Fabrication by Controlled Dielectric Breakdown. PLOS ONE (2014).
5. Bio-inspired Nanocomposite Membranes for Osmotic Energy Harvesting. Joule (2020).
6. Photo-induced ultrafast active ion transport through graphene oxide membranes. Nature Communications (2019).