This study presents a rapid and versatile low-cost sample-to-answer system for SARS-CoV-2 diagnostics. The system integrates the extraction and purification of nucleic acids, followed by amplification via either reverse transcription-quantitative polymerase chain reaction (RT-qPCR) or reverse transcription loop-mediated isothermal amplification (RT-LAMP). By meeting diverse diagnostic and reagent needs, the platform yields testing results that closely align with those of commercial RT-LAMP and RT‒qPCR systems. Notable advantages of our system include its speed and cost-effectiveness. The assay is completed within 28 min, including sample loading (5 min), ribonucleic acid (RNA) extraction (3 min), and RT-LAMP (20 min). The cost of each assay is ≈ $9.5, and this pricing is competitive against that of Food and Drug Administration (FDA)-approved commercial alternatives. Although some RNA loss during on-chip extraction is observed, the platform maintains a potential limit of detection lower than 297 copies. Portability makes the system particularly useful in environments where centralized laboratories are either unavailable or inconveniently located. Another key feature is the platform's versatility, allowing users to choose between RT‒qPCR or RT‒LAMP tests based on specific requirements.

Bioinspired Engineering and Biomechanics Center Xi'an Jiaotong University Xi'an 710049 P R China

Central European Institute of Technology Brno University of Technology Purkyňova 123 Brno 61200 Czech Republic

Department of Chemistry and Biochemistry Mendel University in Brno Zemědělská 1 61300 Brno Czech Republic

Department of Electronic and Computer Engineering The Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong SAR China

Department of Microelectronics Faculty of Electrical Engineering and Communication Brno University of Technology Technická 3058 10 Brno 61600 Czech Republic

ITD Tech s r o Osvoboditelů 1005 735 81 Bohumín Czech Republic

Military Health Institute U Vojenské nemocnice 1200 16200 Praha 6 Czech Republic

Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace; School of Mechanical Engineering Northwestern Polytechnical University 127 West Youyi Road Xi'an Shaanxi 710072 P R China

The Key Laboratory of Biomedical Information Engineering of Ministry of Education School of Life Science and Technology Xi'an Jiaotong University Xi'an Shaanxi 710049 P R China

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Microfluidics chips fabrication techniques comparison