From the teapot effect to tap-triggered self-wetting: a 3D self-driving sieve for whole blood filtration

Achieving passive microparticle filtration with micropore membranes is challenging due to the capillary pinning effect. Inspired by the teapot effect, the authors propose a tap-triggered self-wetting strategy using a 3D-printed polymer tap-trigger microstructure to lower the micropore membrane gating threshold. This resulted in a 35-60 fold reduction in the threshold pressure. A 3D cone-shaped cell sieve incorporating this microstructure achieved a high throughput (above 20 mL/min) while filtering leukocytes from whole blood with comparable purity, higher platelet removal, and lower leukocyte simulation, suitable for single-cell analysis. The tap-triggered self-wetting strategy significantly improved passive microparticle filtration performance.

Yuang Li, Xue Li, Lina Zhang, Xiaofeng Luan, Jiahong Jiang, Lingqian Zhang, Mingxiao Li, Jinghui Wang, Jiangang Duan, Haiping Zhao, Yang Zhao, Chengjun Huang