Optofluidic Waveguide Technologies

Optofluidic waveguide technologies merge microfluidic control with photonic guidance to create chip‐scale devices capable of both manipulating fluids and directing light along the same pathways. By exploiting liquid‐core channels, planar substrates and engineered refractive‐index contrasts, these systems offer dynamically reconfigurable optical elements that adapt in real time to changes in fluid composition or flow. Core architectures include antiresonant reflecting optical waveguides, liquid‐filled channels defined by solid cladding and multimode interference structures, each delivering distinct advantages in sensitivity, compactness and fabrication simplicity. This symbiosis of fluidics and photonics has driven breakthroughs in label‐free sensing, high‐throughput biochemical analysis and point‐of‐care diagnostics, enabling ultrasensitive detection of biomolecules, refractive‐index measurements and multiplexed assays within portable, low‐cost platforms.

Research from Nature Portfolio

Recent studies have demonstrated the power of integrated optofluidic waveguides for pathogen detection and high‐fidelity analysis. A novel edge‐computing approach employs a minimal deep neural network on a compact device to classify fluorescence signals from multiple targets flowing through a liquid‐core waveguide chip, achieving real‐time, amplification‐free multiplexed detection with near‐100 % accuracy. Foundational work on liquid‐core optical waveguides has shown on‐chip sample preparation and fluorescence interrogation capable of detecting viral nucleic acids across a dynamic range of over ten orders of magnitude without biochemical amplification, underscoring the potential for rapid, portable diagnostics. In addition, multimode interference waveguides have been leveraged to create spatial–spectral excitation patterns that encode both wavelength and channel location information, enabling single‐virus sensitivity in scalable multiplex assays that can distinguish multiple pathogens in a single run.

Research from all publishers

Advances external to the portfolio have further expanded the capabilities of optofluidic waveguide devices. An adaptive time‐modulation technique in an integrated biosensor uses dual‐scale temporal excitation to switch seamlessly between digital and analog detection modes, covering target concentrations from attomolar to nanomolar with a single fluidic channel. Low‐cost planar waveguide sensors manufactured via vacuum‐less processes integrate suspended glass waveguides with microfluidic inlets to achieve real‐time refractive‐index sensing with sub-millipart‐per-million resolution, suitable for mass production. Foundational antiresonant reflecting optical waveguides (ARROWs) have been developed for on‐chip spectroscopic analysis, guiding both fluid and light in the same channel and delivering single‐molecule sensitivity in biochemical assays, thereby highlighting the versatility of ARROW architectures for integrated microsensors.

Optofluidic Waveguide Technologies publication trend

The graph below shows the total number of articles in optofluidic waveguide technologies across all publications each year (not limited to Nature Index journals).

Technical terms

Optofluidic waveguide: A microfabricated channel in which both light and fluid are confined and guided simultaneously.

Liquid‐core waveguide: A waveguide whose core region is filled with fluid, enabling dynamic refractive‐index control.

Multimode interference (MMI) waveguide: A structure that produces characteristic interference patterns by supporting multiple optical modes.

Antiresonant reflecting optical waveguide (ARROW): A planar waveguide design that traps light in a fluid‐filled core via antiresonant reflection from surrounding layers.

Multiplexing: The simultaneous detection or analysis of multiple targets within a single device or run.

References

1. Optofluidic bioanalysis: fundamentals and applications. Nanophotonics (2017).
2. Adaptive time modulation technique for multiplexed on-chip particle detection across scales.. Optica (2023).
3. Machine learning at the edge for AI-enabled multiplexed pathogen detection. Scientific Reports (2023).
4. Optofluidic analysis system for amplification-free, direct detection of Ebola infection. Scientific Reports (2015).
5. Scalable Spatial-Spectral Multiplexing of Single-Virus Detection Using Multimode Interference Waveguides. Scientific Reports (2017).
6. Low-cost planar waveguide-based optofluidic sensor for real-time refractive index sensing.. Optics Express (2020).
7. Liquid Core ARROW Waveguides: A Promising Photonic Structure for Integrated Optofluidic Microsensors. Micromachines (2016).