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Biomimetic air purification with liquid-gating topological gradient microfluidics

Nature Chemical Engineering volume 1, pages 650–660 (2024)Cite this article

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Abstract

Particle capture is vital for air purification in environmental protection, regional climate regulation and public health. In particular, filters operating with gas–liquid interfaces can provide efficient particle absorption and removal while serving in a maintenance-free manner. Here a liquid-gating topological gradient microfluidics (LGTGM) device is developed for air purification inspired by the liquid-assisted filtration mechanism of the human respiratory system. The LGTGM device is based on the continuous generation of microbubbles from a supplied gas flow. Due to the large specific interfacial surface area, together with tailored wettability in the device, particulate pollutants in the microbubbles preferentially transfer across the gas–liquid interface and enter a collection liquid. Benefiting from the fine regulation of bubble generation dynamics, multiple LGTGM devices can be combined in series or parallel to achieve efficient air purification as well as high-throughput processing. Moreover, the application potential of LGTGM is demonstrated for smoke filtration, disease prevention and visual detection.

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Fig. 1: Schematic diagram of the biomimetic air purification system.
Fig. 2: Generation of LGTGM.
Fig. 3: Study of the bubble generation process by topological gradient microfluidics.
Fig. 4: Bubble-aided air purification process based on LGTGM.
Fig. 5: Verification of the purification efficiency and extended applications of LAPS.

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Data availability

All data are available within the article and its Supplementary Information.

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (T2225003 and 32271383), the National Key Research and Development Program of China (2022YFB4700100), the Nanjing Medical Science and Technique Development Foundation (ZKX21019), the Clinical Trials from Nanjing Drum Tower Hospital (2022-LCYJ-ZD-01) and the Guangdong Basic and Applied Basic Research Foundation (2021B1515120054).

Author information

Authors and Affiliations

  1. Department of Rheumatology and Immunology, Nanjing Drum Tower Hospital, School of Biological Science and Medical Engineering, Southeast University, Nanjing, China

    Hanxu Chen, Lingyu Sun, Lijun Cai, Yuanjin Zhao & Luoran Shang

  2. Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, China

    Yu Wang & Yuanjin Zhao

  3. Shanghai Xuhui Central Hospital, Zhongshan-Xuhui Hospital, and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, China

    Luoran Shang

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  3. Yu Wang
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Contributions

Y.Z. and L. Shang conceived the idea and designed the experiment; H.C. conducted experiments and data analysis; H.C., L. Shang and Y.Z. wrote the paper. H.C., L. Sun, Y.W., L.C. and L. Shang contributed to scientific discussion of the paper.

Corresponding authors

Correspondence to Yuanjin Zhao or Luoran Shang.

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The authors declare no competing interests.

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Peer review information

Nature Chemical Engineering thanks Taotao Fu and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–22 and Discussion.

Reporting Summary

Supplementary Video 1

Generation of bubbles from a nozzle featured with topological confinement.

Supplementary Video 2

Generation of bubbles by LGTGM with a single nozzle.

Supplementary Video 3

Generation of bubbles by LGTGM with parallel nozzles.

Supplementary Video 4

Particle transfer at the gas–liquid interface.

Source data

Source Data Fig. 2

Statistical source data.

Source Data Fig. 3

Statistical source data.

Source Data Fig. 4

Statistical source data.

Source Data Fig. 5

Statistical source data.

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Chen, H., Sun, L., Wang, Y. et al. Biomimetic air purification with liquid-gating topological gradient microfluidics. Nat Chem Eng 1, 650–660 (2024). https://doi.org/10.1038/s44286-024-00128-z

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