Sample Collection – A Prerequisite for Successful Analysis

news July 02 2017

Regardless of your research focus, sample collection is likely to be an essential part of your experimental workflow. Unfortunately, the quality of collected samples is easily compromised during storage and transport due to nucleic acid and antigen degradation caused by biological factors, enzymatic activity and environmental conditions.

Regardless of your research focus, sample collection is likely to be an essential part of your experimental workflow. Unfortunately, the quality of collected samples is easily compromised during storage and transport due to nucleic acid and antigen degradation caused by biological factors, enzymatic activity and environmental conditions. Samples destined for microbial community profiling e.g., soil and feces, are particularly susceptible, not only to nucleic acid degradation, but also to changes in the overall microbial composition, since some microorganisms continue to grow after collection, unless sample deactivation takes place. Furthermore, transportation of pathogen-containing biological samples may be challenging for both safety and financial reasons.

At Nordic BioSite, we realize that proper sample collection is paramount to ease of working, successful experiments and reliable data, and to facilitate this, we have tailored our portfolio to include a wide range of sample collection tubes, devices and reagents to meet the varied needs of academic and clinical researchers. 

These collection devices are filled with reagents that:

Preserve the nucleic acid content of the sample
Stabilize the sample for transport and storage at ambient temperature
Render the sample non-pathogenic for safe transport and handling

Saliva and Swabs


Saliva and swab analysis is gaining traction throughout research and diagnostics e.g., study of the oral microbiome, study of disease biomarkers, and non-invasive genetic testing in saliva. Obtaining and preserving a good saliva or swab sample is critical to success in these areas. For simple and non-invasive saliva collection and preservation, we offer Norgen Biotek’s collection devices for room temperature preservation of DNA or RNA for up to 5 years or 2 months, respectively. The preservatives contained in these devices are aqueous storage buffers that simultaneously stabilize nucleic acids, while ensuring rapid cell lysis and complete microbial inactivation. Preserved nucleic acids can be isolated from saliva and swabs using most commercially available isolation kits. For DNA analysis, these saliva collection and preservation devices are available as both research-use only or CE-marked products.

For swab collection and preservation, we offer solutions from Norgen Biotek and Zymo Research. For DNA preservation in swabs, we offer Norgen Biotek’s Swab Collection and DNA Preservation Kit, which allows storage for up to 2 years at room temperature. Zymo Research supply swabs in collection tubes with their all-in-one nucleic acid preservation reagent, DNA/RNA ShieldTM, which preserves both DNA and RNA for up to 2 years or 1 month, respectively, when samples are stored at room temperature.

Stool Samples


Quantitative nucleic acid profiling of stool samples has taken off in recent years, fuelled largely by the explosion in microbiome research. Accurate data analysis in this fast-growing field is hampered by a number of technical obstacles, one being proper sample collection and preservation. Shifts in microbial community composition during uncontrolled sample handling and storage create bias that greatly challenges the validity of microbiomics data. One way to reduce this bias is to preserve such samples, in order to capture a molecular snapshot at the exact point of sample collection and thus increase confidence in the data output.

To this end, we offer a range of stool collection devices containing specialized preservatives to stabilize and protect nucleic acids while simultaneously deactivating microbes to yield an accurate microbial profile. Specifically, we offer Norgen Biotek’s Stool Nucleic Acid Collection and Preservation Tubes, Stool Nucleic Acid Collection and Preservation System, and a complete Fecal Swab Collection and Preservation System, all of which accommodate 2 g of stool sample, and stabilize both DNA and RNA at ambient temperature for 2 years or 7 days, respectively. For smaller sample amounts (30 mg), we also offer the Fecal DNA Collection and Preservation Mini Tubes from Norgen Biotek. DNA can be preserved in these tubes for up to 27 months at room temperature. The mini tubes also contain an aliquot of beads for convenient mechanical lysis of stool samples.

DNA/RNA ShieldTM from Zymo Research is also available in Fecal Collection Tubes, permitting room temperature storage of stool samples (1 g) for up to 1 month (for RNA) or 2 years (for DNA).

Whole Blood and Liquid Biopsy

For whole blood and liquid biopsy collection and preservation, we supply a complete range of cell-free (cf) DNA, RNA and whole blood collection tubes and reagents from Streck, Cytomark and Norgen Biotek.

Streck’s cfDNA blood collection tubes (BCT) contain a preservative that stabilizes nucleated blood cells and prevents genomic DNA release, paving the way for high-quality cfDNA isolation for use in a range of downstream applications (e.g. liquid biopsy, assay development, sequencing, real-time PCR). Streck’s cfRNA BCT contains a patented preservative that stabilizes cfRNA in plasma and prevents the release of non-target background RNA during sample processing and storage. With Streck’s BCT, cfDNA and cfRNA is stable for 14 days or 7 days, respectively, at ambient temperature. Streck’s BCT are available as both research-use only or CE-marked products.

In addition to blood collection tubes for nucleic acid stabilization, Streck also provide Cyto-Chex BCT for the preservation of whole blood samples for immunophenotyping by flow cytometry. The preservative in Cyto-Chex BCT maintains the integrity of the white blood cell cluster of differentiation (CD) markers for up to 14 days at room temperature for convenient transport, storage and processing. Streck’s Cell Preservative can also be purchased as a standalone reagent, and is ideal for the storage and stabilization of bone marrow aspirates, surgical tissue samples, fine needle aspirates and peripheral and umbilical cord blood for up to 7 days at room temperature.

For a complete stabilization solution for phenotyping, we offer the TransFix® range from Cytomark, which stabilizes cellular antigens and prevents cellular degradation in a variety of sample types including: whole human and animal blood, cerebrospinal fluid (CSF), bone marrow and circulating tumor cells. The range includes CE-marked EDTA Vacuum Blood Collection Tubes, Sample Storage Tubes (without coagulant), specialized EDTA CSF Sample Storage Tubes, and Phlebotomy Packs for the drawing and stabilization of whole blood samples. For flexibility, Cytomark’s CE/IVD cellular antigen stabilization reagent can be purchased alone in a variety of sizes (TransFix Bulk). Cytomark’s collection devices and reagents ensure sample stabilization upon refrigeration for up to 14 days.

Norgen Biotek provides cfDNA Preservative Tubes for research use, which allow room temperature preservation of cfDNA for up to 30 days, or 8 days at 37 °C for even greater flexibility. DNA/RNA ShieldTM from Zymo Research is also suitable for storage and stabilization of blood samples, and is available in specialized Blood Sample Collection Tubes or as a more concentrated stand-alone preservative for flexibility in storing larger volume samples (2x concentrate). Finally, Norgen Biotek offers a specialized Blood DNA Preservative Buffer (3x) for DNA stabilization in high volume samples, suitable for 2 weeks storage at room temperature. Note: DNA/RNA ShieldTM lyzes cells and is therefore not suitable for samples destined for cell-free nucleic acid analysis.


Streck Cell-Free DNA Urine Preserve is a formaldehyde-free aqueous reagent that stabilizes cellular components and cfDNA in urine for up to 7 days across a wide temperature range (6 °C – 37 °C). The preservative enhances the stability of cfDNA and prevents lysis of nucleated blood cells and release of cellular genomic DNA. Isolated cfDNA is highly suited to a range of downstream applications, such as prenatal diagnosis, disease diagnosis and treatment efficacy monitoring, and organ transplant rejection monitoring.

Zymo Research offers a specialized Urine Conditioning Buffer, which is a highly concentrated preservative to facilitate convenient storage of large volumes of urine. Urine in this buffer can be stored for up to 1 month at room temperature. The Urine Collection Kit from Zymo Research combines the Urine Collection Cup and the Urine Conditioning Buffer offering you an all-in-one solution for urine collection and preservation.

From Norgen Biotek, we offer a Urine Preservative Single Dose, which ensures long-term stability of RNA, miRNA, DNA and proteins for up to 2 years at room temperature. This reagent is highly versatile, stabilizing cell-free macromolecules, exfoliated cells and microorganisms. The same preservative is also available as a dried powder in Norgen Biotek’s Urine Collection and Preservation Tubes. For greater flexibility, these tubes are available in 3 convenient sizes.

Microbial Samples

Within the rapidly expanding field of microbiomics, intense efforts are underway to improve the efficiency of cell lysis and nucleic acid isolation, as well as the accuracy of sequencing workflows for reliable microbial profiling. While accurate profiling depends on an entirely optimized workflow, problems stemming from poor sample collection and storage can greatly skew the results before the experiments even begin, i.e. poor quality starting material = poor quality data!

For microbial sample collection and preservation, Zymo Research provide a range of swabs and tubes with DNA/RNA ShieldTM, with or without their proprietary high-density Bashing BeadsTM for highly efficient mechanical lysis of all microbial samples, including hard-to-lyze gram-positive bacteria, yeast and filamentous fungi, from feces and soil samples. Bashing BeadsTM for microbial lysis comprise a mixture of 0.1 mm and 0.5 mm ceramic beads and are validated for highly efficient lysis of a broad spectrum of microorganisms.

To allow you to optimize and standardize your entire microbiomics workflow, Zymo Research launched the ZymoBIOMICS product line in 2016, a one-of-a-kind complete microbiomics range, which includes DNA/RNA shield™, a selection of DNA and microbial community standards, and a broad range of low-bioburden nucleic acid isolation kits in tube, 96-well or magnetic bead format for automation.

Tissue Samples

DNA/RNA ShieldTM from Zymo Research is suitable for collection and storage of all tissue types and can be custom-filled into customer-supplied vials or collection tubes to meet the varied needs of researchers. To facilitate a smoother sample collection and tissue lysis process, Zymo Research also offers lysis tubes containing DNA/RNA ShieldTM and Bashing BeadsTM for highly efficient mechanical lysis of all tissue types. With DNA/RNA ShieldTM, DNA or RNA is stable for up to 2 years or 1 month at room temperature, respectively.


Norgen Biotek’s Milk DNA Preservation and Isolation kit provides an all-in-one solution for the collection, preservation and isolation of DNA from milk at room temperature. Milk samples are stable for 1 month at room temperature or 1 week at 37 °C, and DNA from both mammalian and bacterial cells can be isolated from as little as 100 μl milk.

Accessories and Equipment

To complete the sample collection range and provide you with even more flexibility, we offer Sterile Individually Wrapped Swabs from Norgen Biotek and Urine Collection Cups from Zymo Research. These devices can be used with or without preservatives of your choice, according to your specific needs. Norgen Biotek also offers packs of sample mailing envelopes, which fulfil both OSHA standards and IATA regulations for safe and convenient shipping of biological samples, providing you with a convenient shipping solution and ease-of-mind.

For those who work in the field, we can provide the TerraLyzerTM from Zymo Research, a handheld mechanical disruption device for cordless, portable, and convenient homogenization of difficult-to-lyse biological and environmental samples. This device allows researchers to ”Take the Lab to the Field” and allows on-the-spot lysis of samples at the sites of collection. Although ideal for those who carry out fieldwork, the TerraLyzerTM is also suitable for lab-based work and is an excellent solution to those who don’t have access to high-throughput mechanical disruption equipment.

To afford you greater flexibility and convenience, all of Zymo Research’s sample collection devices can be custom-filled depending on your needs, so if you don’t see what you are looking for in our product listing, please get in touch with us and we will work with you to find an optimal solution. For more general information or pricing on any of the products featured here, and to find out which sample collection product is right for you, please do not hesitate to get in touch with us at