Singlicate bead-based immunoassay for biomarker quantitation in sub-microliter volume sample.

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Diagnostics

Background:

• Point-of-care testing (PoCT) is crucial for disease diagnostics.
• Detecting biomarkers from minimal sample volumes is challenging for PoCT.

Purpose of the Study:

• To develop a user-friendly method for biomarker detection using minimal sample volumes.
• To enhance sensitivity and reduce sample volume requirements for PoCT.

Main Methods:

• Introduced Forward scattering Correction Using a Single-bead (FoCUS) platform.
• Utilized tiny beads and a small chip for sample analysis.
• Employed a novel signal correction strategy using simultaneous forward scattering signals.

Main Results:

• Achieved a 1000-fold reduction in required sample volume.
• Decreased relative standard deviation of sample signals by 2.7-fold.
• Improved detection limits by 4.3-fold.
• Successfully detected myoglobin from 0.1 μL of sample.

Conclusions:

• FoCUS significantly reduces sample volume requirements for biomarker detection.
• The platform demonstrates high sensitivity and improved detection limits for PoCT.
• FoCUS shows potential for multiplex biomarker immunoassays in resource-limited settings.