Vitrex Vacusence Serum Gel and Clot Activator Tubes contain inert gel; during centrifugation, the gel forms a stable barrier between serum and blood cells. The tubes allow to obtain more serum than regular tubes due to the cleaner separation of serum from the clot. The range of application is: clinical chemistry, immunology, protein electrophoresis, serology, microbiology and toxicology.