A Comparison: Plasma Separation Cards vs. DBS vs. Intravenous Collection

Updated: Nov 9, 2021

There are various methods of blood sample collection for clinical analysis that are available to medical professionals and remote to laboratory consumers. All play a role in this growing industry, and plasma separation offers a versatile solution. In fact, many professionals see plasma collection as a superior choice. This is especially true when compared with dried blood spot cards or storing blood in tubes after venipuncture sampling.


Below is a breakdown of the differences between the three methods and when/why you should use Telimmune Plasma Separation Cards.




Plasma Separation vs. Dried Blood Spot Cards

An important difference between dried blood spot (DBS) and plasma separation cards is identified in the name of each respective technology. DBS cards collect and store whole blood for analysis while Telimmune cards have a filtration layer that removes cells and allows the plasma to be collected. The red blood cells are intentionally trapped in the top membrane layer of the card – A manner similar to a pasta strainer that filters out the unneeded elements.


Why plasma as opposed to whole blood?

A plasma sample is ready to be analyzed whereas the whole blood stored in DBS cards is not. The samples collected on DBS cards must undergo extensive sample preparation that costs time and money. Moreover, plasma separation cards cards collect a defined volume of plasma, making the determination of analyte concentration much simpler.


DBS cards are subject to hematocrit effects. Simply put, people have varying amounts of red blood cells per volume (hematocrit volume), and this introduces volumetric uncertainty during diagnostic testing. Telimmune cards are not subject to hematocrit effects.

In terms of volume, most DBS cards require significantly more blood than Telimmune Plasma Separation Cards. Many DBS cards require 100µL or more to be applied, making it potentially uncomfortable for an individual who might endure multiple finger pricks to obtain enough blood. This may make DBS cards a far more difficult option for remote sampling than the one drop of blood and two drops for the Duo version.

The sample on the Telimmune card stabilizes when dried in a matter of minutes, even remote conditions. In many cases the samples can be stable for weeks or months following blood applications. This is not a possibility with DBS cards because the lack of plasma separation means that metabolite concentrations can change within minutes.

Cheap pricing remains the reason that DBS is a viable option for select usage cases where neither volume, stability, nor sample preparation prior to testing are issues. However, users should be wary with DBS cards as extra costs and time may be required during the sample prep phrase.

Conversely, plasma separation cards may be a better fit for those with remote sampling needs, stability concerns, or a need for a measured amount of plasma to make assay extraction easier.


Plasma Separation vs. Blood Draw w/ Tubes

Venipuncture into vacuum tubes is far more invasive than a fingerstick, which is all that is required to obtain a drop of blood needed for a plasma separation card. Venipuncture draws, while useful in some circumstances, may be considered cumbersome for many needs.

Blood collection draws require around 20ml of blood, which is 400x more blood than the Telimmune Duo and 800x more than the Telimmune Uno. These blood draws are also wasteful in that more than 90% of the blood collected is not needed and disposed of as biohazardous waste.


Be it blood vials or vaccinations, millions of people worldwide have a phobia of needles. If the inefficiency or phobias are not enough, blood collection centers are centralized and necessitate patients being onsite, which is an issue for many with time constraints and/or unreliable transportation. For these reasons and more, patient drop-out rates in clinical trials are very high at over 30%.


Moreover, venipuncture is an expensive technique, and the costs rise even higher for labs that change sample formatting, or instrument companies that are required to revalidate their tests with new collection data. Our solution can be easily purchased online or by a qualified purchase order and can be as cheap as $9 per card depending on volume.


As previously mentioned, Telimmune Plasma Separation Cards are considered by many to be far less traumatic in that they require only a drop or two of blood, testing can be completed remotely, and the sample generated is already devoid of red blood cells. The remote collection element associated with the cards may also help to reduce the dropout rate in clinical trials. Our card provides an alternative solution to venipuncture by providing a volumetric and stable sample in a manner that is simple, convenient, and safe.


Summary

DBS cards, venipuncture, and plasma separation cards all have their own niches in the blood collection and storage market. We believe that our solution is the proper fit for many usage cases and would love the opportunity to speak with you about your own blood collection needs and what assays may align with our cards.


To learn more or start a conversation, please email info@telimmune.com, follow us on LinkedIn, and stay up to date with this blog page.






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