Manually pressurized droplet digital PCR chip for rapid SARS-CoV-2 diagnostics

Area of Science:

• Biotechnology
• Molecular Diagnostics
• Microfluidics

Background:

• Droplet digital PCR (ddPCR) excels in detecting low viral concentrations, outperforming quantitative real-time PCR (RT-qPCR).
• Early virus detection is crucial for timely diagnosis and treatment.

Purpose of the Study:

• To introduce a novel, portable polydimethylsiloxane (PDMS) ddPCR chip.
• To demonstrate the chip's capability for pump-free, manual operation and AI-powered droplet analysis.
• To validate the chip's performance using a SARS-CoV-2 assay with isothermal strand invasion-based amplification (SIBA).

Main Methods:

• Development of a portable PDMS ddPCR chip operated via manual pressurization.
• Generation of monodispersed droplets in a monolayer for easy imaging.
• Utilizing artificial intelligence for droplet analysis and counting.
• Application of the chip with a SIBA-based SARS-CoV-2 assay.

Main Results:

• The portable ddPCR chip successfully generated monodispersed droplets without external pumps.
• AI-driven analysis enabled efficient droplet counting and quantification.
• The SIBA assay on the ddPCR chip provided accurate viral load approximation for SARS-CoV-2 samples.
• The system demonstrated potential for rapid, point-of-care diagnostics.

Conclusions:

• The novel PDMS ddPCR chip offers a portable and user-friendly platform for microfluidic PCR.
• This technology enables quantitative SIBA assays for virus detection, including SARS-CoV-2.
• The system shows promise for accessible, point-of-care viral diagnostics.