Written by: Katie Draves
Table of Contents:
- Viral-Column-based extraction method
- Magnetic Bead method
- Extraction method differences
- Which method is better?
Since the onset of the COVID-19 Pandemic in 2020, it has been of the utmost importance for researchers, and scientists to be able to accurately make COVID-19 diagnoses. Such diagnoses are essential in not only determining which individuals are at risk but also in adding to the collective Pandemic research pool that has been ever-growing since 2020.
While there are indeed many ways in which a COVID-19 diagnosis is produced, three items that are particularly in high demand, is the Transmedia Kit (6ml tubes that contain an RNA Stabilization solution), the Viral Nucleic Acid Extraction Kit (which isolates the Viral RNA from either swabs or saliva), and the UniPLUS RT-qPCR Master Mix (helps to identify whether or not there is a SARS-COV-2 virus in the sample).
Beyond product demand, let us move into the actual process of coming to a COVID-19 diagnosis.
Step one is collecting a sample- this is done commonly by nasal or oral swab or even saliva. (Read more about this in our previous blog: Researchers Guide to Collecting the SARS-COV-2 Sample)
Step two, and the one we shall focus on today, is that of RNA Extraction, which can be done in a few different methods.
The first method is a Viral-Column-based extraction method.
According to kbDNA, Column-based RNA extraction is one of the best techniques among the options available, playing a vital role in ion exchange methods, as it provides a robust stationary phase for a rapid and reliable buffer exchange and thus nucleic acid extraction. This method is fast and reproducible, and its main drawback is the need for a small centrifuge. Vacuum-based systems can also be used in place of centrifugation to separate impurities. Researchers can also combine the organic extraction method with the spin column method for faster and greater RNA yield. This method is fast (20 minutes) and amenable to large-scale and high-throughput processing, including automated methods. Protein or DNA contamination is possible if the sample amount is large or remains incompletely homogenized or lysed. Incomplete lysis can also lead to low yields of viral RNA. Automation can be complex and expensive due to need for setting up centrifugation or vacuum-based separation systems.” -Viral RNA Isolation Methods Reviewed: Spin vs. Magnetic (kbdna.com)
(Graphic sourced from kbDNA.com)
In addition to Column-based RNA extraction being one of the best techniques available, our IBI Viral Nucleic Acid Extraction Kit, in particular, can adapt to automated platforms, which makes it very versatile.
Moving on, the next method for RNA extraction is the Mag-Bead (Magnetic Bead) Method.
According to kbDNA, “the magnetic bead-based method relies on the use of magnetic beads and reagents optimized for RNA extraction. The beads have a paramagnetic core, usually coated with silica for nucleic acid binding. Sample is lysed in a buffer with RNase inhibitors and then incubated with the magnetic beads, allowing the particles to bind RNA molecules. The magnetic beads can then be quickly collected by being placed in proximity to an external magnetic field. The supernatant is removed, and beads are subsequently washed in a suitable wash buffer with removal of the magnetic field. This process can be easily repeated for multiple washes. The RNA is eluted from the magnetic beads with RNase-free water into solution, and the supernatant (containing the pure RNA) can then be transferred.”- Viral RNA Isolation Methods Reviewed: Spin vs. Magnetic (kbdna.com)
(Graphic sourced from kbDNA.com)
Beyond the science of each particular method, there are a few notable differences between these extraction methods.
For starters, while the Magnetic bead-based method, requires a magnetic stand, the Column- based instead requires a centrifuge or vacuum. Next, while there is no concern for clogging with the magnetic bead-based method (because of how tiny the mag beads are), there is a potential clogging concern with the column-based. And thirdly, while the column-based method has a high level of purity, the Magnetic bead-based actually has the highest level of purity.
Method differences aside, both the column-based, alongside the mag-bead contain no organic solvent hazardous waste and are high-throughput friendly. And most importantly both of these methods aid in the diagnosis of COVID-19, which is of utmost importance in the pandemic state in which we live in still.
Now that you are familiar with these two method types, you might be wondering, which method type is better suited for me and my lab?
Starting with “column-based” kits, these are ideal for labs that are studying virus infections. Take for example the currently relevant SARS-COV 2 which was discovered in bats in China, which as well all know eventually made its way into humans. Column-based kits are best suited for labs that are not running thousands of samples per week.
While in contrast, Mag-Bead extraction, and more specifically the ViraMag Kit is almost exclusively done via a robotic system, making the whole process automated. And such robotic systems are able to run thousands of tests per day – much more than a person could do manually themselves.
So, in terms of deciding the ideal method for your lab, it is truly dependent upon how your lab operates and the systems you utilize every single day. If your lab is more automated, and already has a robotic system, it might make more sense to choose the Mag-Bead. While on the flip side, if your lab does not use an automated system, it might be better to choose a Column-based method.
Still, at the end of the day, both of these RNA extraction methods – Column-based & Mag-Bead both work perfectly fine in aiding in the process of producing a COVID-19 diagnosis. With us still living in an ever-pressing pandemic state, it is vitally important that such extraction methods remain readily available for researchers -such researchers who are still working day and night to stop COVID-19 in its tracks, and provide valuable research in the process.
Here at IBI Scientific, we care strongly about the various needs and potential concerns of our customers and community. We also support the ever-growing number of research centers that are working diligently to fight COVID-19 via RNA Extraction alongside any other potential viral infections.
To purchase any of our various life science research-approved products, click the following pages:
Viral Nucleic Acid Extraction Kit
ViraMag DNA/RNA Extraction Kits
Still have questions? Email us at info@ibisci.com and we would be happy to assist you!