An Enclosed Paper Microfluidic Chip as a Sample Preconcentrator Based on Ion Concentration Polarization

Area of Science:

• Analytical Chemistry
• Microfluidics
• Biotechnology

Background:

• Sensitivity is crucial for microfluidic paper-based analytical devices (μPADs) in detecting low analyte concentrations.
• Ion concentration polarization (ICP) is a promising technique for bio-sample preconcentration in μPADs.
• Traditional open-channel μPADs face challenges like sample contamination and evaporation.

Purpose of the Study:

• To develop an enclosed paper-based microfluidic platform for enhanced preconcentration using the ICP effect.
• To overcome limitations of open-channel μPADs, such as evaporation and contamination.
• To improve the performance of ICP-based preconcentration in paper devices.

Main Methods:

• Fabrication of an enclosed paper chip using a Parafilm embedding technique.
• Utilizing the ion concentration polarization (ICP) effect for sample preconcentration.
• Characterization of the enclosed device's performance compared to traditional open-channel μPADs.

Main Results:

• Achieved over 100-fold concentration enhancement in the enclosed paper device.
• Minimized sample evaporation and reduced contamination risk due to the enclosed structure.
• Observed improved ICP performance, including better concentration plug profiles and increased durability.

Conclusions:

• The enclosed paper-based microfluidic platform effectively enhances sample preconcentration via ICP.
• The novel design offers significant advantages over open-channel μPADs for sensitive detection.
• This technology holds potential for improved bio-sample analysis and low-concentration analyte detection.