Serum separator

Longnecker, M. P., Bernstein, L., Bird, C. L., Yancey, A. K. and Peterson, J. C. (1996). Measurement of organochlorine levels in postprandial serum or in blood collected in serum separator tubes . Cancer Epidemiol. Biomarkers Prev., 5(9), 753-755. 

Blood collection tubes, e.g. serum separator tubes, K2EDTA, K3EDTA, Lithium, Microtubes, Cryovials (NuncTM-tubes). 

Other useful parameters are whipping time and estimation of syneresis (serum separation from the foam). 

After the digestion is complete, add 3 ml of 10 mM Tris—HC1, pH 8, to the gel suspension. Separate the gel from the antibody solution by using a serum separator tube or by centrifugation. 

Before beginning the terminal collection procedures have all serum separation tubes for blood collection labeled and all tubes for tissue collection labeled and filled with 5-10 ml 10% formalin (3.7% formaldehyde). Organs from the same mouse can be pooled in the same tube as they can simply be embedded in a single block for histological analysis. 

To avoid hemolysis remove the needle from the syringe and push the blood into a serum separation tube. Do not exceed the volume indicator on the tube (frosted area). 

Individual blood samples are collected from all animals in various groups at the time of sacrifice. Blood is obtained via intracardiac stick under methoxyflu-rane anesthesia and collected into EDTA microtainers and Serum Separator microtainers for complete blood count (CBC) and serum chemistry evaluation, respectively. Clinical chemistry is performed by a commercial resource (e.g., ANTECH Diagnostics) (see Note 8). 

Figure 4-22. Densitometric analysis of serum separation. When electrophoresis is complete, the cellulose acetate film is removed and stained. Excess dye, not bound to protein, is removed by destaining and the film is transferred to a bath in which the cellulose acetate becomes transparent. The film is placed in a scanner in which it is moved across the light path of a spectrophotometer recording the absorbance of the blue stained protein peaks. The result is a densitometric scan whose peaks can be integrated to quantitate the protein profile of the serum.

E421 Egensperger, H.K. and Day, B.S. (1988). Compatibility of five serum separation devices with primary container sampling on the Kodak Ektachem 700 analyzer. Clin. Chem. 34, 1182-1183, Abstr. 146. 

Serum separator tubes are available (Table 2-2) that contain an inert, thixotropic, polymer gel material with a specific gravity of approximately 1.04. Aspiration of blood into the tube and subsequent centrifugation displace the gel, which settles like a disk between cells and supernatant when the tube is centrifuged. Relative centrifugal force (RCF) must be at least 1100 Xg for gel release and barrier formation. Release of intracellular components into the supernatant is prevented by the barrier for several hours or, in some cases, for a few days. These separator tubes may be used as primary containers from which serum can be directly aspirated by a number of analytical instruments. 

Laessig RH, Hassemer DJ, Westgard JO, et al. Assessment of the serum separator tube as an intermediate storage device within the laboratory. Am J Chn Pathol 1976 66 653-7. 

Serum samples are conveniently collected in serum separation tubes (SST) tubes. Blood clotting releases serotonin from platelets samples should be centrifuged within 1 hour after collection and stored frozen at -20 °C. Twenty-four-hour urine samples are collected in 2-L brown polypropylene bottles containing 250 mg each of sodium metabisulfite and EDTA as preservatives. Samples are acidified to pH 4 with acetic acid before freezing. 

Maternal serum specimens can be obtained from nonfasting women by standard phlebotomy techniques. UE3 is the least stable of the four analytes currently used for screening, and consequently, requirements for collection, storage, and shipment are dictated by this analyte. The uEj concentration increases in blood at room temperature and at 4 °C, because the conjugated forms can spontaneously deconjugate to form the parent hormone.Therefore collected blood should be allowed to clot and then serum should be removed promptly. If serum separator tubes are used, specimens should be centrifuged promptly after collection. Shipment of whole blood is not preferred. If whole blood is shipped through the mail, next day delivery is essential. UE3 is stable in serum for up to 7 days at 2 C to 4 C (unpublished data, Foundation for Blood Research, Woman and Infant s Hospital, and ARUP Laboratories). The concentration of UE3 increases when sera have been stored for more than 4 days at room temperature. 

Fig. 4-12. HPICE chromatogram of a human serum. - Separator column IonPac ICE-AS2 (precursor of IonPac ICE-AS1) eluent 0.01 mol/L HC1 flow rate 0.8 mL/ min detection suppressed conductivity (cation exchanger in Ag form) (A) strong inorganic acids, (B) phosphoric acid group, (C) pyruvic add group, (D) lactic acid group, (E) hydroxybutyric acid group.

Fig. 8-97. Separation of inorganic and organic anions in serum. - Separator column IonPac AS4A chromatographic conditions see Fig. 8-94 injection 50 pL sample (diluted 1 10).

N6. Notrica, S., Klein, M. W, Miyada, D, S., and Nakamura, R. M., Effect on chemical values of using polystyrene beads for serum separation. Clin. Chem. 19, 792-793 (1973). 

Pulp-Serum Separation. As for freeze concentration, high viscosity contributes to limiting the degree of concentration which can be achieved by membrane concentration. Since the insoluble solids present in citrus juices contribute significantly to viscosity, one consideration for process development is to separate the pulp from the clear serum, prior to concentration. Because consumers recognize that citrus juices are cloudy and contain pulpy material, it becomes a requirement to blend the separated pulp back with the product concentrate (31). 

Figure 1 Average droplet size (d43) and extent of serum separation of oil-in-water emulsions (10 vol% oil, 4 wt% emulsifier, ionic strength 0.2 M, pH 4.7) stabilized by depolymerized pectins (DE 70%) of various molecular weights (a) RSO (b) D-limonene...

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