Feb 26, 2026
Dried plasma spot biobanking protocol
- Taylor P. Johnson1,
- Ariel Saurí1,
- Daniel W. Sirkis1,
- Jennifer S. Yokoyama1,2,3
- 1Fein Memory and Aging Center, Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, USA;
- 2Global Brain Health Institute, University of California, San Francisco, San Francisco, CA, USA;
- 3Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
- Taylor Johnson
Protocol Citation: Taylor P. Johnson, Ariel Saurí, Daniel W. Sirkis, Jennifer S. Yokoyama 2026. Dried plasma spot biobanking protocol. protocols.io https://dx.doi.org/10.17504/protocols.io.e6nvwnqewvmk/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: February 20, 2026
Last Modified: February 26, 2026
Protocol Integer ID: 243886
Keywords: DPS, dried plasma spot, whole blood, Capitainer, SEP10, UCSF, Yokoyama, dried plasma spot biobanking protocol, standard plasma biobanking method, biobanking of plasma, anticoagulated whole blood, phlebotomy tube anticoagulant volume, accurate quantification of analyte, total volume whole blood, proteomic assessment, biobanking, peripheral blood mononuclear cell, analyte, plasma spot, standard phlebotomy
Abstract
This protocol presents methods for collection and biobanking of plasma in the form of a dried plasma spot (DPS) from whole blood drawn by standard phlebotomy. Leveraging Capitainer SEP10 cards, for a shelf stable, consistent 10 ul DPS, this protocol may be inserted in the beginning of any workflow involving fresh anticoagulated whole blood, such as isolation of peripheral blood mononuclear cells (PBMC), in which only 75-150 ul may be available to spare. Resulting DPS are held at room temperature until elution for downstream applications enabling a more flexible workflow compared to standard plasma biobanking methods. Accurate quantification of analytes for proteomic assessment may be achieved by correcting through a dilution factor, considering (i) phlebotomy tube anticoagulant volume and (ii) total volume whole blood drawn. This protocol supplements original work published by Capitainer AB, Uppsala, Sweden.
Materials
- 8.5 ml acid-citrate-dextrose (ACD) or ethylenediaminetetraacetic acid (EDTA) phlebotomy tube (whole blood drawn)
- Capitainer® SEP10 dried blood spot device, Capitainer AB, Uppsala, Sweden
- P200 wide bore tips
- P200 mechanical pipette
- Tissue culture biosafety cabinet
- Storage box lid (9x9)
- 50 ml conical tubes
Protocol materials
70% ethanol
Capitainer SEP10 sampling card pack
Troubleshooting
Problem
Inadequate sampling resulting in an unchanging disc color
Solution
Possible Causes & Solutions:
1. Pipetting too quickly, leading to inadequate sampling: Pipette slowly and steadily.
2. Excess blood left in the pipette tip, reducing the delivered volume: Ensure the full sample is dispensed from the tip. Pipette slowly and steadily.
3. Bubbles introduced from uneven pipetting: Maintain consistent pressure on the pipette plunger to avoid bubble formation in the sampling channel.
Materials preparation
30m
Obtain whole blood drawn into ACD or EDTA phlebotomy tube.
Clean and sanitize tissue culture hood with 70% ethanol , wipe down with Kimwipe, and UV sterilize.
Allow biospecimen to come to Room temperature (00:30:00 post-draw) and briefly spin to remove residual whole blood from the top of tube.
30m
Spray phlebotomy tube, sealed Capitainer SEP10 sampling card pack , and 9x9 box lid into tissue culture hood with 70% ethanol .
Transfer total volume of whole blood into labeled 50 mL conical with 10 mL serological pipette tip to ensure whole blood is uniform prior to sampling.
Note total volume of whole blood.
Proceed with PBMC isolation or other primary phlebotomy tube application using the remaining whole blood volume.
Dried plasma spot generation
40m
Note
For standard SEP10 sampling methods, please see Capitainer AB, Uppsala, Sweden, Capitainer‱ SEP10 dried blood spot device: Instructions for Use, 2025. Available from: Manufacturer website.
Open the Capitainer SEP10 sampling card pack in the tissue culture hood.
Note
Use within 00:30:00 of opening.
30m
Label card with relevant project info prior to sampling on top card lid. Use gentle pressure to maintain integrity of fragile sampling channels.
Fold back the lid of the card to reveal two sampling lanes.
Note
Do not touch the sample inlets.
Gently place card on the edge of the 9x9 box lid to give sampling lanes a lift to ease sampling.
Slowly and smoothly pipette 75 µL of whole blood into one card lane until the sample indicator line has been filled. There should be 5 µL (2-5 ul) whole blood remaining in tip.
Repeat for the second card lane.
Immediately tilt card at 90° angle for two seconds before lying flat.
Keep card flat and under observation for 00:10:00 until control window appears blue to indicate successful sampling. Upon successful sampling, blue color indicator will be faint.
10m
Close card lid flat. Label with any additional study info and tape closed for storage at Room temperature .
Record all observations and storage locations in secure spreadsheet or LIMS database
system
Protocol references
Capitainer. (2025). CAPITAINER-SEP10 instructions for use [PDF]. Capitainer. https://capitainer.com/wp-content/uploads/2025/11/IFU-SEP10.pdf