Emulsion-based isothermal nucleic acid amplification for rapid SARS-CoV-2 detection via angle-dependent light scatter...

Area of Science:

• Biotechnology
• Molecular Diagnostics
• Nanotechnology

Background:

• The SARS-CoV-2 pandemic highlighted the need for rapid and accurate diagnostic tests.
• Existing methods like RT-PCR, while sensitive and specific, can have lengthy detection times.
• Isothermal amplification methods offer potential for faster nucleic acid detection.

Purpose of the Study:

• To develop a novel emulsion loop-mediated isothermal amplification (eLAMP) platform for rapid SARS-CoV-2 detection.
• To investigate the use of angle-dependent light scatter for real-time monitoring of eLAMP reactions.
• To assess the performance of a smartphone-integrated eLAMP system.

Main Methods:

• Compartmentalization of LAMP reactions within water-in-oil emulsions.
• Monitoring changes in emulsion diameter via angle-dependent light scatter (Mie scatter theory).
• Validation using fluorescence-labeled primers and a smartphone-based platform.

Main Results:

• The eLAMP platform demonstrated statistically significant differentiation of SARS-CoV-2 concentrations (10 to 10^5 copies/μL) within 5 minutes at specific angles.
• Assay times were significantly reduced compared to existing LAMP assays.
• A smartphone-based platform achieved similar limits of detection and assay times (<10 minutes).

Conclusions:

• The developed eLAMP platform enables rapid, sensitive, and specific detection of SARS-CoV-2.
• Real-time monitoring via light scatter provides a novel approach for assessing amplification.
• This technology holds promise for point-of-care diagnostics and pandemic preparedness.