Effects of storage temperature and time before centrifugation on ionized calcium in blood collected in plain vacutainer tubes and silicone-separator (SST) tubes.

Effect of serum volume and time of exposure to gel barrier tubes on results for progesterone by Roche Diagnostics Elecsys 2010.

To the Editor: Inert thixotropic gel is commonly used in blood collection tubes for separation of serum or plasma from the cellular components of blood. Eichhorn et al. (1 ) in 1997 suggested that gel tubes (Sarstedt) used in their laboratory were generally reliable, but they found incomplete separation in 3.1% of tubes. Plain tubes are preferred for therapeutic drug monitoring because of the p...

Effect of silicone-separator tubes and storage time on ionized calcium in serum.

Thrombin-Mediated Degradation of Parathyroid Hormone in Rapid Serum Tubes

Background: Measurement of parathyroid hormone (PTH) is important for the clinical assessment of parathyroid disease and calcium homeostasis. Previous studies have demonstrated decreased stability of PTH in serum versus plasma specimens, although the precise mechanism for this difference has not been established. If thrombin activation during clot formation is responsible, the effect should be ...

Influence of centrifugation conditions on the results of 77 routine clinical chemistry analytes using standard vacuum blood collection tubes and the new BD-Barricor tubes

Introduction Although centrifugation is performed in almost every blood sample, recommendations on duration and g-force are heterogeneous and mostly based on expert opinions. In order to unify this step in a fully automated laboratory, we aimed to evaluate different centrifugation settings and their influence on the results of routine clinical chemistry analytes. Materials and methods We coll...

Evaluation of evacuated blood-collection tubes: effects of three types of polymeric separators on therapeutic drug-monitoring specimens.

The potential of three types of separator materials found in conventional blood-collection tubes for interference in therapeutic drug measurements was assessed. None of the separators (based on acrylic, silicone, or polyester polymers) had any significant effect on the concentrations of seven drugs (theophylline, digoxin, phenytoin, phenobarbital, gentamicin, ethanol, and cyclosporine) in blood...