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A Gradient-generating Microfluidic Device for Cell Biology
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Abnormal Liquid Chasing Effect in Paper Capillary Enables Versatile Gradient Generation on Microfluidic Paper
Yu Liu1, Jin-Wen Shangguan1, Bi-Yi Xu1,2
1State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering , Nanjing University , Nanjing 210023 , China.
Analytical Chemistry
|January 10, 2020
Summary
Researchers developed novel microfluidic paper analytical devices (μPADs) for generating 1D and 2D concentration gradients. This technique enables advanced serial sampling for high-throughput analysis and condition screening.
Area of Science:
- Analytical Chemistry
- Microfluidics
- Biomedical Engineering
Background:
- Microfluidic paper analytical devices (μPADs) offer accessible point-of-care testing (POCT) solutions.
- Traditional μPADs have limitations in generating complex concentration gradients.
- Advanced fluid control in microscale is crucial for enhanced analytical functions.
Purpose of the Study:
- To introduce novel methods for generating 1D and 2D concentration gradients on μPADs.
- To enable fast, ordered, and tunable sequential sampling using paper-capillary systems.
- To demonstrate the applicability of the developed technique for arrayed assays.
Main Methods:
- Utilized paper-capillary-based serial sampling with a concaved paper channel sealed with tape.
- Engineered peripheral test pads for continuous liquid consumption from the capillary channel.
- Observed an abnormal liquid chasing effect for reversely ordered sample distribution.
Main Results:
- Successfully generated 1D and 2D concentration gradients with one, two, and three components.
- Demonstrated applicability for 1D serial dilution-based metal ion colorimetry.
- Validated for 2D bacterial antibiotic susceptibility testing to evaluate synergistic effects.
Conclusions:
- The developed paper-capillary serial sampling technique enables efficient gradient generation on μPADs.
- This method facilitates high-throughput sample analysis and information-rich condition screening.
- Paves the way for advanced applications in diagnostics and drug discovery.
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