Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
1.
Journal of Modern Laboratory Medicine ; 35(5):113-117, 2020.
Article in Chinese | GIM | ID: covidwho-1264598

ABSTRACT

Objective: To evaluate whether a domestic novel coronavirus (SARS-CoV-2) nucleic acid detection kit meets the requirements of clinical SARS-CoV-2 nucleic acid detection.

2.
PLoS Biol ; 18(12): e3000978, 2020 12.
Article in English | MEDLINE | ID: covidwho-1044757

ABSTRACT

The recent outbreak of betacoronavirus Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which is responsible for the Coronavirus Disease 2019 (COVID-19) global pandemic, has created great challenges in viral diagnosis. The existing methods for nucleic acid detection are of high sensitivity and specificity, but the need for complex sample manipulation and expensive machinery slow down the disease detection. Thus, there is an urgent demand to develop a rapid, inexpensive, and sensitive diagnostic test to aid point-of-care viral detection for disease monitoring. In this study, we developed a clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated proteins (Cas) 12a-based diagnostic method that allows the results to be visualized by the naked eye. We also introduced a rapid sample processing method, and when combined with recombinase polymerase amplification (RPA), the sample to result can be achieved in 50 minutes with high sensitivity (1-10 copies per reaction). This accurate and portable detection method holds a great potential for COVID-19 control, especially in areas where specialized equipment is not available.


Subject(s)
COVID-19 Testing/methods , CRISPR-Cas Systems/genetics , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Base Sequence , Humans , Reproducibility of Results , Sensitivity and Specificity
3.
J Clin Lab Anal ; 35(1): e23643, 2021 Jan.
Article in English | MEDLINE | ID: covidwho-891884

ABSTRACT

BACKGROUND: We aimed to evaluate the analytical performance of five commercial RT-PCR kits (Genekey, Daan, BioGerm, Liferiver, and Yaneng) commonly used in China, since such comparison data are lacking. METHODS: A total of 20 COVID-19 confirmed patients and 30 negative nasopharyngeal swab specimens were analyzed by five kits. The detection ability of five RT-PCR kits was evaluated with 5 concentration gradients diluted by a single positive sample. The limit of detection was evaluated by N gene fragment solid standard. Two positive clinical specimens were used to evaluate the repeatability and imprecision. Finally, we used six human coronaviruses plasmid and four respiratory pathogens plasmid to check for cross-reactivity. RESULTS: The positive detection rate was 100% for Genekey, Daan, and BioGerm,and 90% for Liferiver and Yaneng in 20 clinical SARS-CoV-2 infection. The coincidence rate of five kits in 10 negative samples was 100%. The detection rate of target genes for Daan, BioGerm, Liferiver, and Yaneng was 100% from Level 1 to Level 3. In Level 4, only Daan detection rate was 100%. In Level 5, five kits presented poor positive rate. The limit of detection declared by each manufacturer was verified. The repeatability for target genes was less than 5% and so did the total imprecision. There is no cross-reactivity of five kits with six human coronaviruses and four respiratory pathogens for ORF1ab and N gene. CONCLUSIONS: Five RT-PCR kits assessed in this study showed acceptable analytical performance characteristics and are useful tools for the routine diagnosis of SARS-CoV-2.


Subject(s)
COVID-19 Testing/methods , Reverse Transcriptase Polymerase Chain Reaction/methods , SARS-CoV-2/genetics , Humans , Limit of Detection , Nasopharynx/virology , Polyproteins/genetics , Reproducibility of Results , Viral Proteins/genetics
4.
Microb Biotechnol ; 13(4): 950-961, 2020 07.
Article in English | MEDLINE | ID: covidwho-116666

ABSTRACT

The pandemic coronavirus SARS-CoV-2 in the world has caused a large infected population suffering from COVID-19. To curb the spreading of the virus, WHO urgently demanded an extension of screening and testing; thus, a rapid and simple diagnostic method is needed. We applied a reverse transcription-loop-mediated isothermal amplification (RT-LAMP) to achieve the detection of SARS-CoV-2 in 30 min. We designed four sets of LAMP primers (6 primers in each set), targeting the viral RNA of SARS-CoV-2 in the regions of orf1ab, S gene and N gene. A colorimetric change was used to report the results, which enables the outcome of viral RNA amplification to be read by the naked eye without the need of expensive or dedicated instrument. The sensitivity can be 80 copies of viral RNA per ml in a sample. We validated the RT-LAMP method in a hospital in China, employing 16 clinic samples with 8 positives and 8 negatives. The testing results are consistent with the conventional RT-qPCR. In addition, we also show that one-step process without RNA extraction is feasible to achieve RNA amplification directly from a sample. This rapid, simple and sensitive RT-LAMP method paves a way for a large screening at public domain and hospitals, particularly regional hospitals and medical centres in rural areas.


Subject(s)
Betacoronavirus/isolation & purification , Coronavirus Infections/diagnosis , Nucleic Acid Amplification Techniques/methods , Pneumonia, Viral/diagnosis , Betacoronavirus/classification , Betacoronavirus/genetics , COVID-19 , China , Coronavirus Infections/virology , DNA Primers/genetics , Humans , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2 , Sensitivity and Specificity , Viral Proteins/genetics
SELECTION OF CITATIONS
SEARCH DETAIL
...