Capitainer®qDBS and Capitainer®B Vanadate is designed for finger-pricking, i.e. using fresh blood. However, you might want to start your validation experiments with venous blood and pipetting it to the cards in the lab. There are some aspects to consider when you do this:.

• Do not use blood older than three days stored in the refrigerator and let blood come to room temperature before using it on the cards.
• All blood samples should be well mixed using a rocker prior to application to the card.
• If you use a syringe dispenser, you should make sure to apply blood to the cards within 5 minutes from last time mixing (also for normal DBS).
• Lyophilized blood products may not work.
• Make sure that the DBS disc is completely dry before removal. A wet disc might  not detach correctly from the card.

We have designed our paper based shipping method to reduce waste and minimise the carbon footprint of your workflows. The packaging approach follows the CDC triple packaging guidelines for DBS specimen collection.[1] We strongly recommend the use of our shipping method.

However, if your analytes are sensitive to humidity and / or temperature, alternative approaches such as storing the samples in aluminium coated plastic bags and inclusion of desiccant pouches should be considered. The approach taken for individual analytes will need to be appropriately validated.

For more guidance, please check the extensive literature on DBS.

The paper “Dried blood spots: Effects of less than optimal collection, shipping time, heat, and humidity” gives an introduction to the topic.

[1] Shipping Guidelines for Dried-Blood Spot Specimens (cdc.gov)

The disc containing the blood is easily accessed from the reverse of the card by peeling away the protective tabs.

The discs can be removed manually with tweezers and put it into a suitable tube or plate for extraction. We recommend a flat tip tweezer.

Capitainer also provides a semi-automated puncher system. The puncher is equipped with a barcode scanner, optical detection of the disc in the wells and an optional cleaning step for the puncher head between each sample. The semi-automated puncher saves time and also ensures traceability of each sample for the downstream analysis process.

The Capitainer puncher system is calibrated at delivery for your 96-well plate of choice.

We highly recommend use of the automated puncher solution for larger projects and/or frequent analysis.

Read more about the puncher at the product page.

After collection of the disc, the sample is eluted. The choice of elution protocol and buffer is dependent on your analyte and downstream analysis. The published methods used with traditional DBS samples are also applicable for Capitainer®qDBS.

After adding your buffer of choice to the tubes or plate wells containing the discs, extract on a shaker for around 30-60 minutes and then transfer the liquid to a clean tube or plate.

To reduce the diluent volume and introduce a clean-up step, the use of spin columns/plates to elute the sample might be considered. This has the benefit of also recovering more of the diluent from the disc (up to 20 microliters).

The eluted samples are ready for analysis on your selected platform. Among the techniques and platforms used with samples from Capitainer are:

Mass spectrometry
Elisa
PCR
Capillary electrophoresis
Immunochemistry
Luminex xMAP®

The review “State of the Science in Dried Blood Spots” describes a range of analytes measurable in DBS samples. These approaches should also be applicable to the quantitative analysis of Capitainer®qDBS samples.

For venous sampling, large volumes of blood are discarded, since only small volumes are typically used for analysis. Self-sampling with Capitainer® reduces this waste. Please, always follow your local regulations regarding waste handling of dried samples.

If not discarded, samples are often stored in biobanks. Venous samples are typically transferred to tubes and frozen at -80 °C. This is costly, consumes a lot of energy and takes up a large amount of space. qDBS samples offer the possibility to biobank samples in a simpler and more cost efficient way.

The paper “Stability of Proteins in Dried Blood Spot Biobanks” discusses the possibilities.