Norgen’s Saliva RNA Collection and Preservation Devices are designed for 1) simple and non-invasive saliva collection and 2) preservation of RNA in saliva samples at ambient temperature. Each of the 50 Saliva RNA Collection and Preservation Devices consists of 3 components: (1) Saliva Collection Funnel and Collection Tube, (2) Collection Tube Cap, and (3) Norgen’s Saliva RNA Preservative contained within a sealed squeezable ampoule. Saliva samples are collected by spitting inside the Collection Funnel which has been assembled with the Collection Tube. After collecting the required volume of saliva the Collection Funnel is removed and the contents of the Preservative Ampoule are then added and mixed with the collected saliva. The Saliva Collection Tube is subsequently sent to the laboratory for RNA isolation and analysis. RNA can be isolated from the preserved saliva samples using Norgen’s Saliva/Swab RNA Purification Kits (Cat# 69100, 69300). Each of Norgen’s Collection Tubes is labeled with a unique serial number that can be used for secure and anonymous tracking of the sample. The Saliva RNA in preserved samples is stable for up to 2 months at room temperature. This kit is ideal for collecting and preserving RNA samples for epidemiological and population studies.
SALIVA RNA PRESERVATIVE
Norgen’s Saliva RNA Preservative is an aqueous storage buffer designed for rapid cellular lysis and subsequent preservation of RNA from fresh specimens. The buffer eliminates the need to immediately process or freeze samples and allows the samples to be shipped to centralized testing facilities at ambient temperature. The components of the buffer allow samples to be stored for up to 2 months at room temperature.
NUCLEIC ACID ISOLATION FROM PRESERVATIVE
Saliva RNA can be isolated from the preserved saliva samples using Norgen’s Saliva/Swab RNA Purification Kits (Cat# 69100, 69300).
Figure 1. Stability of RNA Preserved in Norgen's Saliva RNA Preservative at room temperature for up to 2 months. Saliva samples were collected from numerous donors and mixed, and then an equal volume of Norgen's Saliva RNA Preservative was added to the saliva. The preserved saliva was then stored at room temperature for up to 2 months. Saliva RNA was subsequently isolated at day 0, day 4, day 6, day 16, 1 month and 2 months from 0.25 mL of the saliva/preservative sample usingsupplementary protocol associated withNorgen's Total RNA Purification Kit (Cat. 17200). For visual analysis, 7.5 µL from 50 µL elution was mixed with RNA loading dye and was run on a1x MOPS agarose gel. RNA integrity was maintained after the saliva samples werestored up to 2 months at ambient temperatures in Norgens Saliva RNA Preservative.
Figure 2. Stability of three house keeping genes over a 2 month period. GAPDH, Human 18S rRNA and beta actin genes were monitored from saliva samples stored at ambient temperature with Norgen's Saliva RNA Preservative. RNA was isolated from 250 µL of preserved samples on day 0, day 4, day 6, day 10, day 16, day 30 and day 60 usingNorgen's Total RNA PurificationKit (Cat. 17200). Next, 4 µL of elution was used in 20 µL of the real-time PCR reaction (SYBR Green I) using CFX96 TouchTM Real-Time PCR Detection System (Bio-Rad). All of the genes were preserved and stable over 2 month period.
Figure 3. Norgens Saliva RNA Preservative is able to successfully preserve saliva RNA samples when used outside of the ideal range of 1:1 at room temperature for 3 days. As the amount of saliva added to 2 mL of Saliva RNA Preservative increased from 0.2 mL to 3 mL, RNase protein and β-actin gene were monitored for RNA stability using one-step RT-PCR. The results indicated that the variation of the saliva input volumes did not significantly influence the RNA gene detection.
Figure 4. Detection of Viral, Bacterial and Human RNA from Preserved Saliva Samples. Saliva (2 mL) collected from a single healthy donor was mixed with 2 mL of Saliva RNA Preservative. Norgens COVID-19 positive control from the 2019-nCoV TaqMan RT-PCR Kit (E/RdRP gene) (Cat. TM67200) was spiked into the preserved saliva along with HeLa cells (1.6 m cells /ml ) to generate a contrived sample. From the contrived sample, total RNA was purified using Norgens Total RNA Purification Kit (Cat. 17200) and 5 genes (16s rRNA, COVID-19 E gene, RdRP-P1 and P2 gene and RP) were analyzed by PCR or RT-PCR to detect viral, bacterial and human genes.
When stored at room temperature, unused Norgen Saliva Preservative Tubes are stable through to the collect-before date without any reduction in performance. Please see the device insert or tube label for collect-before date.
Once collected, saliva RNA is stable for up to 2 months when kept tightly sealed and stored at room temperature.
The Collection Tube, the Collection Funnel and the Device Container of each individual Saliva RNA Collection and Preservation Device are recyclable.