Vacuette 9nc trisodium citrate 3.2

A volume of 40 mL of whole blood was collected in-house from 5–7 donors chosen randomly from a pool of volunteers after informed consent was signed. Blood collection was approved by the local Ethics Committee of Danube University Krems (approval date: Jan 14^th 2013). Inclusion criteria for blood donation were an age of between 25 and 45, as well as being in good health on the day of blood donation. This was determined using an evaluation form, whereby conditions such as pregnancy, underweight, or diabetes were deemed exclusion criteria. Citrate-anticoagulated PRP (CPRP) was generated via collecting whole blood into citrate-coated vacutainer tubes (VACUETTE 9NC trisodium citrate 3.2%, Greiner BioOne, Kremsmunster, Austria, #455322) and further processed as described in [67 (link)]. hypACT was prepared by using hypACT inject developed by OrthoSera GmbH (Krems, Austria). Within this device, blood was collected and centrifuged immediately at 1710× g for 5 min at room temperature (RT). As no anticoagulants were present, a fibrin clot formed inside the device, whose content was extracted by pressing the pistil into the syringe in order to obtain hypACT.

Whole blood donations from healthy human volunteers between 25 and 45 years old were used to prepare PRP. The exclusion criteria of donors included pregnancy, underweight or diabetes. Whole blood was collected following standards for blood collection and screened for infections. Whole blood was transferred into a citrate-coated tube (VACUETTE 9NC trisodiumcitrate 3.2%, Greiner BioOne, Cat No. 455322) and centrifuged at 440× g at room temperature for 10 min. The top fraction, containing the platelets, was transferred to a new tube, and centrifuged again at 1710× g at room temperature for 10 min. The platelet pellet was resuspended within one third of the supernatant plasma. PRP from different donors were pooled and stored at −20 °C.

Human whole blood was drawn in-house by approved personnel from voluntary donors after informed consent and approval by the local ethics committee (ESC1020/2020). Donor inclusion criteria were age between 25 and 45 years, as well as healthy based on a self-evaluation form asking for primary diseases such as diabetes or conditions including underweight or pregnancy at time of blood donation. Selection of donors based on gender was done randomly to avoid gender bias. Blood was drawn from 10 donors, 6 female and 4 male. For CPRP preparation, blood was collected from 5 donors per round into citrate-coated vacutainer tubes (VACUETTE^® 9NC trisodium citrate 3.2%, Greiner BioOne, #455322) and processed as described earlier (Kuten et al., 2018 (link)). For preparation of hypACT, blood was collected using the hypACT^TM inject device developed by OrthoSera GmbH (Krems, Austria) and spun immediately at 1,710 × g for 8 min at room temperature (RT). Following the formation of platelet-rich fibrin in the device, the fibrin clot was squeezed by pressing the piston into the syringe to yield hypACT. Blood cell profiles in freshly prepared blood products were determined by a Sysmex XN-1000 Sa-01 cell counter. Blood products were processed immediately.