Exeter Clinical and Health Research Standard Operating Procedure: Blood sample separation and storage SOP Number: NIHRexe/002/GEN Version Number & Date: V1.1 22/02/2017 Review Date: 22/02/2017 Superseded Version Number & Date: v1 05/08/2016 Author: Name: Steven Spaull Position: CRF Technician Approved by: Name: Diane Jarvis Position: CRF Technician Senior Management Agreement: Name: Gillian Baker Role: CRF Manager I agree that appropriate members of my workforce (as named above) have written and approved this SOP for use in clinical research. Page 1 of 5
1. BACKGROUND: It is often necessary to separate either blood plasma or serum from a blood sample by centrifugation and aliquot off the blood plasma or serum supernatant into storage tubes for further future analysis. 2. SCOPE: This SOP applies generically to clinical trials and research projects, clinical and health research in Exeter, unless a trial agreement specifically indicates that another organisations SOP should be used. 3. PURPOSE: The purpose of this generic document is ensuring correct and uniform sample separation and storage. 4. DEFINITIONS AND ABBREVIATIONS Plasma: blood plasma supernatant, including that obtained from specialist tubes Serum: blood serum supernatant 5. ROLES AND RESPONSIBILITIES: It is the responsibility of staff undertaking clinical research to read and use this SOP when carrying out sample processing for any research study that requires centrifugation of samples. This includes samples processed in the NIHR Exeter CRF, and any centrifugation that occurs off site (for example, home visits, or outside clinics). 6. SKILL LEVEL: This procedure should only be carried out by personnel who have undergone the appropriate departmental training. This includes CRF technicians and nurses. 7. EQUIPMENT: Gloves, nitrile Goggles (in case of spillage) Lab coat or disposable apron Centrifuge (either bench-top refrigerated or portable ambient) Page 2 of 5
Spill tray. All blood handling should be carried out on a spill tray to contain any spillage. Disposable plastic pipettes/pipette tips Correctly pre-labelled tubes for storage or plasma/serum samples Tube rack that can be sterilised in the event of spillage Blood spillage kit Sharps bin Clinical waste bag 8. PROCEDURE: N.B. SOP NIHRexe/019/GEN must be read and enacted prior to following the steps outlined here. Sample separation When removing samples from the centrifuge, it is vital to avoid disturbing sediment when pipetting off sera and to avoid disturbing the buffy coat when separating plasma. Taking care to minimise any aerosol effect, remove the lid from the blood tube to be separated. Only deal with one sample at a time. Hold the sample to be separated in one hand, and a clean pipette in the other. Either hold the tube lid in the same hand as the tube, or place it upside down on the bench top or spill tray surface. Never place the screw-thread side of the lid directly on a surface. Squeeze the bulb of the pipette between thumb and forefinger, outside of the tube. Insert the open end of the pipette into the plasma/serum fraction of the sample, taking care not to disturb the red cell sediment or the buffy coat. Gently release the pressure on the bulb of the pipette so that the negative pressure in the pipette aspirates ( sucks up ) the serum. Transfer the plasma/serum to the waiting labelled aliquot tubes by inserting the open end of the pipette about halfway into each aliquot tube and squeezing the bulb until the appropriate sample size has been reached. Repeat this process for each individual aliquot. If required, return to the plasma tube to aspirate more supernatant. DO NOT squeeze the bulb of the pipette outside of a container. Instead, insert the tip of the pipette into the tube, gently squeeze the bulb above the level of the supernatant, then insert the tip of the pipette into the supernatant and aspirate more supernatant. Once aliquoting is complete, put the top back on the plasma/serum tube. Page 3 of 5
Dispose of sample tube and pipette safely: plastics in orange clinical waste bags, blood samples in yellow bag and glass in sharps bin. Ensure plasma sample top is secure, and transfer to plastic sample bag for transfer to genetics lab. Dispose of plasma pipette safely. Pipettes are for single use only. However, where samples have been obtained from the same subject, at the same time and are of the same type, a pipette may be used for more than one sample tube. Caution should be taken to avoid dribbling bodily fluids on to surfaces, however. Spillages Spillage of any bodily fluid should be cleaned according to local procedure. This can be accessed from the Infection Control Site (Decontamination Policy), via the RD&E NHS FT IaN website. It is the responsibility of clinical staff, not housekeeping, if the spillage is in a clinical area. Infection Control Department advise that blood and blood product spillage should be dealt with as follows: Put on protective latex gloves and plastic apron and if splashing is possible, wear eye protection. Where the spillage may contain sharp material, forceps may be used to remove the sharp material, placing it in a sharps bin. If the spillage is large, soak up the excess fluid using paper towels and carefully place these in a yellow clinical waste bag along with used gloves. Wearing a fresh pair of protective latex or nitrile gloves, use a fresh cloth to wipe the area of spillage with warm water and detergent (10,000 ppm chlorine solution) to disinfect. Dry with fresh absorbent towels. Check the Infection Control Manual for the most recent recommendations. Blood spillage kit contents Medium nitrile gloves Cleaning cloths Disposable wipes Hygienic hand rub Sharps bin Page 4 of 5
Labelling of sample vials Each vial will be labelled according to study specific protocols. Each sample must have a unique identifying mark, be placed in an indexed container and have its location and identifying mark recorded electronically. Further, this information must be crossreferenced in some way with the participant s consent form, such that all samples can be tracked back to the consent form signed by the person from whom they were taken, at the time they were taken. Storage of sample vials Samples need to be immediately placed in a -20 o C freezer and then transferred to a -80 o C freezer within one week, as far as is practicable. Study specific samples will be stored in a designated freezer, the site of which will be identified prior to sample collection. Each sample and where it is stored needs to be logged onto the study database, where it should be identifiable, and labelled as sample location folder. Where samples are removed for use, or disposal, this should also be recorded on the study database. 9. DESIRED OUTCOME: Correct, appropriate and safe processing of blood samples, such that integrity and safety of samples and staff is maintained. When followed in combination with NIHRexe/19/GEN and study specific SOPs and protocols, samples should be centrifuged, aliquoted and stored accurately to ensure the maximum scientific value can be garnered from them. 10. REFERENCES: 11. APPENDICES: Page 5 of 5