An automated, fully-integrated nucleic acid analyzer based on microfluidic liquid handling robot technique

On-site nucleic acid testing (NAT) plays an important role for disease monitoring and pathogen diagnosis. In this work, we developed an automated and fully-integrated nucleic acid analyzer by combining the automated liquid handling robot technique with the microfluidic droplet-based real-time PCR assay technique. The present analyzer could achieve multiple operations including sample introduction, nucleic acid extraction based on magnetic solid-phase extraction, reverse transcription and, sample droplet generation, PCR amplification, real-time and dual fluorescence detection of droplet array. A strategy of constructing an integrated compact and low-cost system was adopted to minimize the analyzer size to 50 × 45 × 45 cm (length × width × height), and reduce the instrument cost to ca. $900 with a single analysis cost less than $5. A simple chip was also designed to pre-load reagents and carry oil-covered PCR reaction droplets. We applied the analyzer to identify eight types of influenza pathogens in human throat swabs, and the results were consistent with the colloidal gold method.