DOI

Detection Principle

NucleicAcid-PCR based

Target

ORF1ab, N

Testing Method Category

RT-PCR

Testing Method

in house assay: We have developed a thermostable DNA polymerase, which can mediate DNA synthesis from both RNA as well as DNA templates (Sauter & Marx, 2006). By targeted modifications, we have further improved the accuracy and processivity of this enzyme (Blatter, Bergen et al., 2013), which lays the foundation of the commercialized Volcano3G formulations.

Testing Method - Additional Info

Improved nucleic-acid-based approach to detect SARS-CoV-2, which alleviates the need to purify RNA, reduces handling steps, minimizes costs, and allows evaluation by non-specialized equipment. The use of unprocessed swap samples and the ability to detect as little as three viral genome equivalents is enabled by employing a heat-stable RNA- and DNA-dependent DNA polymerase, which performs the double task of stringent reverse transcription of RNA at elevated temperatures as well as PCR amplification of a SARS-CoV-2 specific target gene. As results are obtained within 2 hours and can be read-out by a hand-held LED-screen.

Reported Performance

Performance evaluated in parallel with a commercial in vitro diagnostic kit (Allplex, Seegene): consistency with regard to positive and negative outcomes, increased sensitivity might be due to the fact that the high temperature reverse transcription step involves several cycles, which allow initial highly stringent amplification of viral target genes. Though the high temperature RT-PCR with Volcano3G was slightly more sensitive, the results correlated extremely well over a wide range of cq-values with the results obtained by the commercial assay (r2=0.980, p<0.0001, Fig. 2D).

Sample Size

43 samples

Peer-reviewed

yes