TransFix ® was developed by medical scientists from UK NEQAS, which is a part of Sheffield Teaching Hospitals

NHS Foundation Trust. TransFix ® was developed out of the requirement to produce stabilised bloodsamples that could be used in External Quality Assurance programs forflow cytometry. 

The first publication on TransFix®as a cellular antigen stabilizing reagent was made in 1999 by D.Barnett et al.

TransFix®has been in circulation in the research world from 1999 until thepresent day, generating a number of scientific publications. In 2005the Sheffield Teaching Hospitals NHS Foundation Trust licensedTransFix®to Cytomark in order to make it more generally available to theclinical and scientific world.


TransFix®Vacuum Blood Collection Tubes

TransFix®Sample Storage Tubes

TransFix®EDTA CSF Sample Storage Tubes



Whole Blood Control - Low - 1.5ml vial Blood Controls(1.5ml)
CD4Stabilised Whole Blood Control - Normal - 1.5ml vial  
BloodControls (1.5ml)

CD4Stabilised Whole Blood Control - Low & Normal - 2 x 1.5ml vial 
Blood Controls (2 x 1.5ml)

CD4Stabilised Whole Blood Control - Low - 1.5ml vial - Sample 
BloodControls (0.5 ml)

CD4Stabilised Whole Blood Control - Normal - 1.5ml vial - Sample 
BloodControls (0.5 ml)

CD4Stabilised Whole Blood Control - Low & Normal - 2 x 1.5ml vials -Sample 
Blood Controls (2 x 0.5 ml)

CerebrospinalFluid Stabilisation with TransFix®EDTA

Cerebrospinal Fluid (CSF) can be stabilised and stored inTransFix® / EDTA for up to 10 days allowingsamples to be batched and transported safely.

TransFix®- Bone Marrow Stabilisation

Bonemarrow examination is an essential procedure for the evaluation of avariety of clinical haematologic disorders and for preclinicaltoxicity studies of anticancer compounds and immuno suppressive agents.

The short processing and analysis time, and the ease withwhich batches of samples can be analysed, has resulted in bone marrow flow cytometry becoming a routine test in clinical laboratories.Research work is currently being performed on the stabilisation of bone marrow aspirates with TransFix® EDTA for up to 10 days following aspiration, allowing samples to bebatched and transported prior to analysis.

TransFix® - Animal Blood Stabilisation

TransFix®can be used to stabilise whole blood from a wide range of differentspecies including mouse, rat, guinea pig, sheep, seal, turtle,ostrich and pig. The volume of TransFix® required to stabilise blood varies considerably in different speciesand users must determine the optimal dilution required. Pleasecontact us for further details.

Setup a range of TransFix® dilutions starting with 0.05ml of TransFix®per ml of whole blood, increasing in 0.05ml steps to 0.2ml. Mix welland store at 4°C for 10 days. After 10 days analyse the TransFix® treated samples by flow cytometry using the same method as before.

Theoptimal dilution of TransFix®for the animal species under examination is the concentration thatgives the same scatter diagram as the fresh blood sample.

TransFix®- Human Blood Stabilisation

ImmuneMonitoring of HIV/AIDS

MonitoringCD4 and CD8 T-cell subsets of human immunodeciency virus(HIV)-infected individuals is performed routinely by flow cytometry.It is the most commonly used method for monitoring the immune statusof HIV-infected individuals. Ordinarily, specimens must be processedwithin 36 hours to obtain reliable CD4+ T-cell absolute counts.

Bloodtreated with TransFix®however, remains stable for up to 10 days when stored at 2-8°C.(Research has also shown that they remain stable for up to 10 dayswhen stored at 22°C and for 4 days at 37°C (1)). TransFix® stabilises cell surface antigens, allowing transport back to alaboratory without deterioration. This is particularly important incountries where the transport infrastructure is poor and unreliable.

TransFix®is also a highly effective anti-viral agent that results in areduction in HIV replication as measured by HIV p24 antigenproduction (2). However, samples must still be handled with universalprecaution protocols.


Subsets of lymphocytes can be distinguished on the basis of cell surface antigens using flow cytometry. Quantitative and qualitative changesin lymphocyte subsets are used to identify and monitor immunological diseases. TransFix® is validated using the BD MultiTest™/TruCOUNT tube technology withthe Lyse/No Wash system. Cell surface antigens shown to be stableafter blood has been treated with TransFix® and stored for 10 days at 2- 8°C include CD3, CD4, CD8, CD45. Thisinformation is specified on our Certificates of Analysis and can beviewed at The wide range of antibodyclones and conjugates available make it essential that end-usersvalidate their reagents with TransFix®

TransFix® Vacuum Blood Collection Tubes

VacuumBlood Collection Tubes are plastic, direct draw tubes used to collectand stabilise venous blood at the point of collection. Tubes areavailable in 3ml or 10ml sizes. Each tube is prefilled withsufficient TransFix® containing K3EDTA for the stabilisation of 3ml or 10ml of blood,respectively. Vacuum Blood Collection Tubes are CE marked. 3ml VacuumBlood Collection Tubes are available in 10, 25, 50 or 100 pack sizes.10ml Vacuum Blood Collection Tubes are available in 15, 30, 60 packsizes. 2 pack samples size are also available.

For detailedinformation please send a mail to and we ensure a response within 24 hrs!!!