Osmotic Processor for Enabling Sensitive and Rapid Biomarker Detection via Lateral Flow Assays

Area of Science:

• Biomarker analysis
• Point-of-care diagnostics
• Biospecimen processing

Background:

• Urine is a valuable biospecimen for in vitro diagnostics.
• Urine-based lateral flow assays offer low-cost, point-of-care testing.
• Assay sensitivity is often limited by low urinary biomarker concentrations.

Purpose of the Study:

• To develop a device for concentrating urinary biomarkers.
• To improve the sensitivity of lateral flow assays.
• To enable detection of low-concentration analytes in urine.

Main Methods:

• Development of a static osmotic processor using a dialysis membrane and polymer solution.
• Water extraction from urine via osmotic pressure.
• Concentration of biomarkers like human chorionic gonadotropin and SARS-CoV-2 nucleocapsid protein.
• Evaluation using lateral flow assays and mass spectrometry.

Main Results:

• The osmotic processor efficiently extracted 5-15 ml/h of water.
• Concentrated specimens significantly improved lateral flow assay detection limits.
• Mass spectrometry indicated up to a 200-fold increase in SARS-CoV-2 nucleocapsid protein concentration.
• Test band intensities with concentrated specimens mimicked 100-fold higher concentrations.

Conclusions:

• The osmotic processor effectively concentrates urine biomarkers.
• This technology enhances the sensitivity of existing lateral flow assays.
• The device shows potential for sensitive detection of dilute analytes in urine, particularly in low-resource settings.