Blood samples are collected in a variety of different blood tubes such as: heparin, EDTA, sodiumfluoride, and gel separation tubes. Blood collected in heparin- and sodiumfluoride tubes are used to perform analyses of clinical and haematological parameters (including LDL/HDL cholesterol, HbA1c, and triglycerides) and are therefore no longer available for release. The results of these analyses can be obtained upon request.
Plasma/buffycoat samples derived from EDTA collection tubes and serum samples derived from gel separated tubes are stored in the Lifelines Biobank and can be requested for research purposes.
DNA samples are extracted from the buffycoat fractions and can likewise be requested for research purposes.

From collection to storage, Lifelines adheres to stringent quality control protocols to ensure that the samples are fit for use in all standard blood analysis protocols. Standard operating procedures for all the steps described below can be provided by Lifelines on request.

Please note that the text below describes the procedures as they are employed during the ongoing third assessment. The baseline- and second assessments differ in various ways, and Lifelines recommends consulting their respective wiki pages to learn more about the procedures employed at those times.

Blood was typically collected between the hours of 07:00 and 10:00, and participants were asked to refrain from consuming any food or liquids (with the exception of water) after 22:00 on the evening preceding visit 2.
Blood was primarily collected through venopuncture of the median cubical vein of the right arm using Venoject® needles in combination with Vacutainer® blood collection tubes, although butterfly needles and venopuncture of other locations (such as the left arm or the wrist) have also been employed if the previous was not an option.

The following blood samples are placed into cryostorage after processing by the Lifelines laboratory.

• Blood (plasma) samples are collected from Lifelines participants (ages 8+) using BD Vacutainer® 10.0 mL K2E (EDTA) 18.0mg Plus blood collection tubes.
• Blood (buffycoat) are collected from Lifelines participants (ages 8+) using BD Vacutainer® 10.0 mL K2E (EDTA) 18.0mg Plus blood collection tubes.
• Blood (serum) samples are collected from Lifelines participants (ages 8+) using BD Vacutainer® 10.0 mL SST II Advance blood collection tubes.

The following blood samples are used to perform a variety of diagnostic blood tests.

• Blood (plasma) samples are collected from Lifelines participants (ages 8+) using BD Vacutainer® 4.5 mL LH (Lithium Heparin) PST™ II Plus blood collection tubes.
• Blood (plasma) samples are collected from Lifelines participants (ages 8+) using BD Vacutainer® 4.0 mL K2E (EDTA) 7.2mg Plus blood collection tubes.
• Blood (plasma) samples are collected from Lifelines participants (ages 8+) using BD Vacutainer® 4.0 mL NaF 3.0mg Na2EDTA 6.0mg Plus blood collection tubes.

After collection the blood tubes are placed in a refrigerated (using ice packs), insulated transport box. The temperatures in these boxes are continuously monitored (LogTag TRIX-8) as part of our quality control procedures. These transport boxes are then shipped to the Lifelines laboratory, typically arriving between the hours of 10:00–12:00.

Upon arrival at the Lifelines laboratory the blood collection tubes are divided into two distinct categories:

• Blood collection tubes meant for diagnostic testing are refrigerated (at 4 degrees Celsius) and sent onwards to the UMCG in a refrigerated transport box.
• Blood samples to be stored by Lifelines are either immediately centrifuged (according to the protocols detailed below) or refrigerated (at 4 degrees Celsius) until this is possible.

The temperature measurements taken during transport are reviewed and saved to our labotatory information management system (LIMS).

• 10.0 mL K2E (EDTA) 18.0mg Plus blood collection samples | 15 minutes @ 2500RCF and 4 degrees Celsius, no brake
• 10.0 mL SST II Advance blood collection samples | 10 minutes @ 2500RCF and 18 degrees Celsius, no brake

Blood (plasma) and blood (serum) samples are divided into 900 μl fractions by the Tecan Freedom EVOware® robot, a semi-automated system that combines pipetting, robotics, and scheduling of multiple devices.
These aliquots can be identified by a unique 2D barcode printed on the bottom of the tubes, and are held within a 1D barcoded rack (LVL technologies Safe® 96 IT or equivalent). The exact location of each individual sample is logged and continuously tracked in our LIMS.
During sample processing special care is given to note deviations, such as hemolysis and lipemia, and to register these in our LIMS.

Aliquots are kept refrigerated (at 4 degrees Celsius) until they can be moved into a cryofreezer (-80 degrees Celsius), which is typically within 10 hours after sample collection.