Stool Collection Tubes with RNA Stabilizer

FAQs

• 1. What are the Stool Collection Tubes with RNA Stabilizer used for?

  The Stool Collection Tubes with RNA Stabilizer are used to collect and stabilise stool samples for RNA-based molecular research. They preserve RNA integrity directly at the point of collection, supporting downstream applications such as RT-qPCR, gene expression analysis, and RNA sequencing.

• 2. Which stool collection tube should I use for DNA-based applications?

  For DNA-based applications, such as microbiome testing by 16S rRNA sequencing, shotgun metagenomics, or qPCR, we recommend primarily using the separately available Stool Collection Tubes with DNA Stabilizer, as they provide a higher DNA yield.

  The Stool Collection Tubes with RNA Stabilizer are optimised for RNA preservation but additionally stabilise DNA, allowing complementary DNA analysis when RNA is the primary target and both nucleic acids are to be analysed from a single, standardised collection format.

• 3. How do I extract RNA or DNA from stool samples stabilised in the tubes?

  Stabilised stool samples are compatible with common RNA extraction kits as well as standard DNA extraction methods. Before extraction, process the stabilised sample as follows:

  1. Centrifuge an aliquot of the stabilised sample (e.g. 1.8 ml) for 10 minutes at maximum speed.
  2. Remove the supernatant.
  3. Use the stool pellet for the subsequent RNA or DNA extraction according to your kit protocol.

  For optimal results, we recommend the InviTrap® Spin Universal RNA Mini Kit for RNA extraction and the PSP® Spin Stool DNA Basic Kit for DNA extraction. Detailed, validated workflows are described in the application notes available in the Resources section.

• 4. How long is RNA stable in the Stool Collection Tubes with RNA Stabilizer?

  Stool RNA is stabilised for up to 3 months at 4 °C, up to 4 weeks at 25 °C, and up to 2 weeks at 37 °C. For storage beyond these validated periods, stabilised samples can be frozen.

• 5. Why is RNA stabilisation important for stool samples?

  RNA degrades rapidly after collection due to endogenous RNases and microbial activity. Immediate stabilisation preserves the RNA profile present at the time of sampling, reducing preanalytical variability and ensuring reliable, reproducible downstream results.

• 6. Which downstream applications are validated for the stabilised samples?

  The Stool Collection Tubes with RNA Stabilizer are validated for RT-qPCR, gene expression analysis, and RNA sequencing.

• 7. Can stool samples be stored at room temperature after collection?

  Yes. Stool RNA remains stable for up to 4 weeks at 25 °C, enabling sample collection, storage, and shipment without a routine cold chain.

• 8. Can the stabilised stool samples be frozen for long-term storage?

  Yes. For longer-term storage of RNA and DNA, stabilised stool samples can be frozen.

• 9. Do the tubes require cold-chain shipping?

  No. The validated room-temperature stability of up to 4 weeks at 25 °C, and up to 2 weeks at 37 °C, allows standard shipping without temperature-controlled logistics, reducing costs for multicentre and decentralised studies.

• 10. How do I collect a stool sample with the tubes?

  Each tube features an integrated sampling spoon, allowing simple and contamination-free transfer of stool material into the pre-filled tube. A separately available Stool Catcher further simplifies collection from the toilet.

• 11. Are the tubes suitable for at-home or decentralised sample collection?

  Yes. The hygienic collection format, integrated spoon, optional Stool Catcher, and room-temperature stability make the tubes well suited for self-collection at home, field studies, and multicentre research projects.

• 12. Are the tubes barcoded?

  Yes. Each tube is barcoded, enabling full sample traceability from collection through transport, storage, and analysis.

• 13. Are the Stool Collection Tubes with RNA Stabilizer CE-IVD certified?

  No. The Stool Collection Tubes with RNA Stabilizer are for Research Use Only (RUO) and are not intended for use in diagnostic procedures. For CE-IVD stool collection, see the Stool Collection Tubes with DNA Stabilizer (CE-IVD),

• 14. Can RNA and DNA be analysed from the same stool sample?

  Yes. Because the reagent stabilises both RNA and DNA, researchers can combine transcriptomic analyses (e.g. gene expression and RNA sequencing) with complementary DNA-based assays from one sample, reducing sampling burden and improving data comparability.

  However, for DNA-based applications, such as microbiome testing by 16S rRNA sequencing, we recommend primarily using the separately available Stool Collection Tubes with DNA Stabilizer,, as they provide a higher DNA yield.

• 15. How much stool sample should be collected per tube?

  The recommended stool input is 1 g of stool per tube. Using the integrated spoon ensures that an appropriate amount of sample is transferred into the pre-filled stabiliser.

• 16. How should the tubes be stored before use?

  Unused tubes should be stored at room temperature. The shelf life is indicated on the product label.