Microfluidic device with chemical gradient for single-cell cytotoxicity assays

Area of Science:

• Biomedical Engineering
• Cell Biology
• Toxicology

Background:

• Cytotoxicity assays are crucial for evaluating chemical safety and drug efficacy.
• Current methods often lack the resolution to assess single-cell responses to varying chemical concentrations.
• Microfluidic devices offer potential for high-throughput, precise cellular analysis.

Purpose of the Study:

• To develop and validate a novel microfluidic device for single-cell cytotoxicity assays.
• To enable high-efficiency, high-density single-cell entrapment within a controlled chemical gradient.
• To assess the feasibility of using this platform for quantitative, time-resolved cytotoxicity evaluations.

Main Methods:

• Fabrication of a microfluidic device integrating a chemical gradient generator and a microcavity array.
• Demonstration of rapid (30 s), high-efficiency (88 ± 6%) single-cell entrapment without cell damage.
• Validation using potassium cyanide (KCN) exposure across a range of concentrations (0-100 μM).
• High-throughput imaging and analysis of 4000 single cells to determine viability.

Main Results:

• The device achieved high-density single-cell loading in microcavities.
• A serial 2-fold logarithmic chemical gradient was successfully generated and applied.
• Cell viability was accurately determined for single cells exposed to varying KCN concentrations.
• Image acquisition and analysis of 4000 cells were completed efficiently (within 10 min).

Conclusions:

• The developed microfluidic platform enables precise, single-cell level cytotoxicity assessment.
• This technology facilitates high-throughput screening and detailed toxicological studies.
• The device is a valuable tool for basic biomedical research and chemical safety evaluations.