Microfluidic immunoassays as rapid saliva-based clinical diagnostics

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Oral Medicine

Background:

• Current point-of-care (POC) diagnostics offer limited binary health status indications.
• Sophisticated bioassays are needed for quantitative measurement of complex disease biomarkers.
• Monitoring disease onset and progression requires robust diagnostic tools.

Purpose of the Study:

• To develop a clinical POC diagnostic for rapid, quantitative measurement of oral disease biomarkers in saliva.
• To integrate sample pretreatment and electrophoretic immunoassays on a microfluidic platform.
• To demonstrate the utility of the device for measuring matrix metalloproteinase-8 (MMP-8) in periodontal disease.

Main Methods:

• Development of a monolithic disposable cartridge for a compact analytical instrument.
• Integration of microfluidic sample pretreatment (filtering, enrichment, mixing) with electrophoretic immunoassays.
• Quantification of salivary MMP-8 using minimal saliva (20 microliters) within 10 minutes.

Main Results:

• Demonstrated rapid (<10 min) quantification of MMP-8 in saliva from healthy and periodontally diseased subjects.
• Validated microfluidic assay results against conventional MMP-8 measurements.
• Showcased the device's applicability for proteinaceous biomarker detection in biological fluids.

Conclusions:

• A microchip-based POC diagnostic enables rapid and reliable measurement of salivary MMP-8.
• This technology facilitates quantitative assessment of oral disease biomarkers.
• The developed platform is applicable for monitoring disease onset and progression.