Duplex kits for detection of SARS-CoV-2
one-step real-time PCR
Each of the 4 kits is based on one-step RT-qPCR using fluorescently labelled probes in one channel (FAM) and internal positive control in the other channel (HEX). The detection method is based on officially recommended WHO designs for detection of SARS-Cov-2 and usage of our proprietary GEMINI™ probe technology. Our solution comprises of two alternative kits for primary testing and two alternative kits for confirmation of positively assessed samples.
gb Sarbeco N
gb SARS-CoV-2 RdRP
– a one-step RT-qPCR method according to WHO protocols, detected genes: N / E (primary tests), RdRP / N (confirmation tests)
– a choice of a particular kit for the primary and confirmation testing is up to the laboratory´s preferences
– the duplex design enhances a sensitivity and decreases a risk of contamination
– a target gene in FAM channel, an internal positive control (control of PCR inhibition) in HEX channel
– GEMINI™ probe technology results in a high sensitivity of detection and a lower background
– to check the efficiency of sampling and RNA extraction process, the detection procedure can be supplemeted with a kit for detection of human RNA gb Human B2M mRNA kit
– in case of a contamination by PCR products, a laboratory can immediately switch to an alternative primary and confirmation kit
– LOD of assays is lower than 3 copies of viral RNA per reaction (95% CI)
– the identical temperature profile for all the kits
The primary test kits (gb Sarbeco N, gb Sarbeco E ) based on detection of viral N gene and E gene, respectively, are intended for primary testing of all samples. The assays target conservative sequences of Sarbecovirus group.
The confirmation test kits (gb SARS-CoV-2 RdRP, gb SARS-CoV-2 N) based on detection of viral RdRP gene and N gene, respectively, are recommended for confirmation of samples positively assessed by the primary testing. The assays target SARS‑CoV‑2 specific sequences.
Detailed description of the kits
- the detection method is based on a one-step RT-qPCR – no need to open a microtube during the testing process
- the design of two successive duplex tests ensure enhanced sensibility of both tests
- each CE IVD kit comprises
- Specific qPCR Assay – an Internal Positive Control (IPC) is included
- OneStep Master Mix
- Positive Control
- Negative Control
- the reaction mixture is prepared by mixing two components of the kit + a biological sample (a scheme here). Each kit contains all components necessary to perform a one-step RT-qPCR detection of viral RNA.
- as all the kits have FAM detection system and HEX Internal Positive Control, they can be run on two-channel thermocyclers. The kits are therefore compatible with most thermocyclers worldwide.
- FAM probes in all the kits are modified by GEMINI™ technology to enhance sensibility and specificity of detection
- there are identical amplification profiles for all the kits
- LOD of the assays is lower than 3 copies (determined by probit analysis, 95% CI) of viral RNA in one reaction (such sensitivity corresponds to a theoretical minimum reachable by PCR methods)
Quality of RNA sample
For those labs that need to confirm the quality of the analyzed sample to prevent false negative results, our gb Human B2M mRNA kit may be a helpful solution. It enables to check both, whether swab samples have been collected efficiently and whether the RNA extraction method works efficiently as well.
The kit is based on detection of transcripts of B2M gene, a human reference gene ubiquitously present in all human samples. Using gb Human B2M mRNA kit, the whole preanalytical process is checked. In case that any sample deviates from the series (or it is not detected at all), a new collection and the reanalysis of the sample is recommended.
Consumption of the two kits
At the beginning of testing by the two kits, we recommend you acquire both kits in ratio 5:1 (500 rxn of primary test : 100 rxn of confirmation test). An order ratio for subsequent orders can be adjusted to expected ratio of positive samples (10:1 to 20:1 or even less is reasonable).
Back-up solution if a contamination occurs
Although microtubes with PCR products must not be open in laboratories, an accidental contamination can occur after all, especially if the lab provides high throughput testing. If it happens, the laboratory testing is threatened and the currently used kits cannot be employed any more.
For easy recovery from such a critical scenario we recommend to use only one type of the primary test and one type of the confirmation test. If the contamination by PCR products occurs, switch the currently used kits to that alternative pair of kits.
Choice of primary kit is up to laboratory´s preference. Both kits (gb Sarbeco N / gb Sarbeco E) detect viruses of Sarbecovirus group including SARS-CoV-2. Our recommendation: use only one kit on standard basis. If contamination by PCR products occurs, switch the kit to another one.
We recommend to order primary test kits and confirmation kits in ratio 10:1 (1000 rxn of primary test + 100 rxn of confirmation test) or even less.
CE IVD one-step RT-qPCR kit contains reagents to provide 100/500 PCR reactions (20 μl volume of each reaction).