Single-cell analysis by electrochemical detection with a microfluidic device.

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Microfluidics

Background:

• Single-cell analysis is crucial for understanding cellular heterogeneity.
• Traditional methods often require large sample volumes and can be time-consuming.
• Developing sensitive and efficient single-cell analysis techniques is an ongoing challenge.

Purpose of the Study:

• To develop a novel electrochemical method for single-cell analysis.
• To integrate multiple steps including cell handling, lysis, and detection on a microfluidic chip.
• To demonstrate the quantification of intracellular analytes in individual cells.

Main Methods:

• A microfluidic chip with a double-T injector and an end-channel amperometric detector was designed.
• Single cells were loaded and lysed using electric fields.
• Intracellular analytes were electrokinetically transported and electrochemically detected.
• External standardization was employed for quantification.

Main Results:

• The method successfully integrated cell injection, lysis, and electrochemical detection on a single chip.
• Ascorbic acid (AA) in single wheat callus cells was quantified as a model compound.
• The electrochemical detection offered high selectivity, resulting in simple electropherograms.
• The technique demonstrated potential for analyzing various electroactive species in single cells.

Conclusions:

• A novel, integrated electrochemical microfluidic system for single-cell analysis was successfully developed.
• The method provides a sensitive and selective approach for quantifying intracellular analytes.
• This technique holds promise for broader applications in single-cell metabolomics and diagnostics.