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Microsyst Nanoeng ; 7: 94, 2021.
Article in English | MEDLINE | ID: covidwho-1528008


Coronavirus disease 2019 (COVID-19) has emerged, rapidly spread and caused significant morbidity and mortality worldwide. There is an urgent public health need for rapid, sensitive, specific, and on-site diagnostic tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In this study, a fully integrated and portable analyzer was developed to detect SARS-CoV-2 from swab samples based on solid-phase nucleic acid extraction and reverse transcription loop-mediated isothermal amplification (RT-LAMP). The swab can be directly inserted into a cassette for multiplexed detection of respiratory pathogens without pre-preparation. The overall detection process, including swab rinsing, magnetic bead-based nucleic acid extraction, and 8-plex real-time RT-LAMP, can be automatically performed in the cassette within 80 min. The functionality of the cassette was validated by detecting the presence of a SARS-CoV-2 pseudovirus and three other respiratory pathogens, i.e., Klebsiella pneumoniae, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. The limit of detection (LoD) for the SARS-CoV-2 pseudovirus was 2.5 copies/µL with both primer sets (N gene and ORF1ab gene), and the three bacterial species were successfully detected with an LoD of 2.5 colony-forming units (CFU)/µL in 800 µL of swab rinse. Thus, the analyzer developed in this study has the potential to rapidly detect SARS-CoV-2 and other respiratory pathogens on site in a "raw-sample-in and answer-out" manner.

Clin Chem ; 67(4): 672-683, 2021 03 31.
Article in English | MEDLINE | ID: covidwho-1165392


BACKGROUND: Infectious disease outbreaks such as the COVID-19 (coronavirus disease 2019) pandemic call for rapid response and complete screening of the suspected community population to identify potential carriers of pathogens. Central laboratories rely on time-consuming sample collection methods that are rarely available in resource-limited settings. METHODS: We present a highly automated and fully integrated mobile laboratory for fast deployment in response to infectious disease outbreaks. The mobile laboratory was equipped with a 6-axis robot arm for automated oropharyngeal swab specimen collection; virus in the collected specimen was inactivated rapidly using an infrared heating module. Nucleic acid extraction and nested isothermal amplification were performed by a "sample in, answer out" laboratory-on-a-chip system, and the result was automatically reported by the onboard information platform. Each module was evaluated using pseudovirus or clinical samples. RESULTS: The mobile laboratory was stand-alone and self-sustaining and capable of on-site specimen collection, inactivation, analysis, and reporting. The automated sampling robot arm achieved sampling efficiency comparable to manual collection. The collected samples were inactivated in as short as 12 min with efficiency comparable to a water bath without damage to nucleic acid integrity. The limit of detection of the integrated microfluidic nucleic acid analyzer reached 150 copies/mL within 45 min. Clinical evaluation of the onboard microfluidic nucleic acid analyzer demonstrated good consistency with reverse transcription quantitative PCR with a κ coefficient of 0.979. CONCLUSIONS: The mobile laboratory provides a promising solution for fast deployment of medical diagnostic resources at critical junctions of infectious disease outbreaks and facilitates local containment of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) transmission.

COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , Laboratories , Mobile Health Units , Pathology, Molecular/methods , RNA, Viral/analysis , Adult , Automobiles , COVID-19/epidemiology , COVID-19 Nucleic Acid Testing/instrumentation , Female , Humans , Lab-On-A-Chip Devices , Male , Microfluidic Analytical Techniques/instrumentation , Microfluidic Analytical Techniques/methods , Middle East Respiratory Syndrome Coronavirus/chemistry , Molecular Diagnostic Techniques/instrumentation , Molecular Diagnostic Techniques/methods , Pandemics , Pathology, Molecular/instrumentation , Robotics , SARS-CoV-2/chemistry
Engineering (Beijing) ; 6(10): 1130-1140, 2020 Oct.
Article in English | MEDLINE | ID: covidwho-743961


Fast and accurate diagnosis and the immediate isolation of patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are regarded as the most effective measures to restrain the coronavirus disease 2019 (COVID-19) pandemic. Here, we present a high-throughput, multi-index nucleic acid isothermal amplification analyzer (RTisochip™-W) employing a centrifugal microfluidic chip to detect 19 common respiratory viruses, including SARS-CoV-2, from 16 samples in a single run within 90 min. The limits of detection of all the viruses analyzed by the RTisochip™-W system were equal to or less than 50 copies·µL-1, which is comparable to those of conventional reverse transcription polymerase chain reaction. We also demonstrate that the RTisochip™-W system possesses the advantages of good repeatability, strong robustness, and high specificity. Finally, we analyzed 201 cases of preclinical samples, 14 cases of COVID-19-positive samples, 25 cases of clinically diagnosed samples, and 614 cases of clinical samples from patients or suspected patients with respiratory tract infections using the RTisochip™-W system. The test results matched the referenced results well and reflected the epidemic characteristics of the respiratory infectious diseases. The coincidence rate of the RTisochip™-W with the referenced kits was 98.15% for the detection of SARS-CoV-2. Based on these extensive trials, we believe that the RTisochip™-W system provides a powerful platform for fighting the COVID-19 pandemic.