Sensitivity-improved blocking agent-free fluorescence polarization assay through surface modification using...

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Biochemistry

Background:

• Fluorescence polarization (FP) assays are crucial for biomolecule quantification.
• Integrating FP assays with microfluidic devices offers potential for onsite analysis.
• Nonspecific adsorption of biomolecules in polydimethylsiloxane (PDMS) microfluidic devices reduces assay sensitivity.

Purpose of the Study:

• To develop a surface modification for PDMS microfluidic devices to enhance FP assay sensitivity.
• To eliminate the need for blocking agents in FP assays within microfluidic devices.
• To improve the quantification of low-abundance analytes using FP immunoassays (FPIA).

Main Methods:

• Surface modification of PDMS microfluidic devices using polyethylene glycol (PEG).
• Evaluation of PEG modification's efficacy in preventing nonspecific protein adsorption.
• Demonstration of an FP immunoassay (FPIA) utilizing the modified microfluidic devices.

Main Results:

• The polyethylene glycol-based surface modification effectively inhibited nonspecific protein adsorption.
• The modified microfluidic devices demonstrated significantly improved sensitivity for FP assays.
• The enhanced FP immunoassay (FPIA) showed improved performance for low-abundance analyte detection.

Conclusions:

• Polyethylene glycol surface modification is a viable strategy to enhance FP assay sensitivity in microfluidic devices.
• This approach overcomes the limitations of nonspecific adsorption in PDMS-based systems.
• The developed method holds promise for sensitive onsite quantification of biomolecules, especially low-abundance targets.