Separated plasma

Haemonetics Bowl Technology. Haemonetics disposable bowl technology has evolved from the original plasma separation chamber. The two principal shapes of bowls are the Latham bowl and the blow-molded bowl (Fig. 4). 

Quantitative assay of biotinidase activity including evaluation for the presence of a Km defect requires 1 ml of plasma. Serum samples can be also used. Biotin therapy does not affect the assay [ 32 ]. The activity in plasma may decrease during storage (see Pitfalls and Limitations , below). We recommend the use of ethylene-diami-netetraacetic acid (EDTA)-plasma separated from whole blood and assayed within... 

Plasma separated from heparin- or EDTA-treated blood. The required minimal volume is 1 ml. Store immediately at -80°C. 

The need to transfuse blood components such as plasma, platelets, factor VIII, in addition to red blood cells (RBC) has generated the development of plasmapheresis (plasma separation from whole blood) and more generally that of apheresis (fractionation of blood components). Plasma collection from donors by centrifugation of blood bags began only in 1944. This technique was extended to therapeutic plasma purification in 1950, but RBCs were fragilized by the centrifugation and the plasma was not completely platelet-free. 

Plasma separation by membrane microfiltration was proposed in 1978 by Salomon et al. [1] as a substitute to centrifugation and its clinical potential confirmed in 1980 by Samtleben et al. [2]. This technique yields a high-quality cell-free plasma that avoids for the recipient the immunological hazards of contamination by platelets and cellular fragments and is less traumatic for red cells, if precautions are taken to avoid hemolysis during filtration. 

In contrast to hemodialysis that uses ultrafiltration membranes, plasma separation (also called plasmapheresis) requires microfiltration membranes with a pore size from 0.2 to 0.6 pm, in order to transmit all proteins and lipids, including LDL cholesterol (2000kDa) and retain completely platelets (2 pm diameter), red blood cells (8 pm diameter) and white blood cells. Thus, membrane plasmapheresis can yield high-quality platelet-free plasma and red cells can be either continuously returned to the donor or saved in another bag for blood transfusion. But it is important, in the case of plasma collection from donors, to minimize the membrane area, in order to reduce the cost of disposable hollow-fiber filters and to avoid the risk of hemolysis (free hemoglobin release) due to RBC damage by contact at the membrane if the pressure difference across the membrane is too high. 

Membranes used for therapeutic plasma separation have the same characteristics as those used for plasma collection from donors, but their area is larger as the amount... 

Table 18.3 Commercially available membrane filters for plasma separation and fractionation.

Medical applications are among the most important in the membrane market, with hemodialysis, blood oxygenators, plasma separation and fractionation being the traditional areas of applications, while artificial and bioartificial organs and regenerative medicine represent emerging areas in the field. 

As discussed above, marijuana contains four constituents (viz,I-IV) similar in structure and chemical properties whereas the metabolites are more polar and in the case of V and VI, more acidic than I. Thus it seemed plausible that I-IV could be separated from V and VI in plasma based upon pH adjustment and solvent extraction properties. Compounds I-IV were found to be extractable at ambient pH of 7.4 using petroleum ether whereas V and VI could be extracted at pH 4.1 using 99 1, benzene isopropanol. Once the initial plasma separation was effected a chromatographic separation was feasible using normal phase conditions for I-IV and reverse phase conditions for V and VI. Each technique is detailed in the following sections. 

Several preanalytical factors can cause a false elevation of the measured plasma ammonium concentration. These include prolonged tourniquet application, hemolysis, specimen transportation at room temperature, delay in plasma separation, and even ambient ammonium from cleaning agents or cigarette smoke. These fac-... 

Plasma separation for preparing plasma fractionates should be performed at low temperatures to prevent bacterial contamination and protein denaturation. Sakai et al. [1989] found that organic polymer membranes, when used for low-temperature plasma... 

Plasma perfusion In 1974 patient plasma separated by plasmapheresis was for the first time passed through activated charcoal and artificial resin in order to absorb toxins. In this way, the patient s own purified plasma is reinfused together with the solid components of the blood. This procedure produces fewer side effects and is easy to carry out. 

FPSA Fractioned plasma separation and adsorption is a very efficient and multifactorial method, employing membranes and adsor-bants. (86) It is additionally characterized by the use of microparticles (2.0-3.5 pm), which are recirculated in suspension using high-speed flow (2-4 1/min) to optimize the in-line filtration process. In a further development, a special sidfone filter is applied. 

Temporary substitution of the liver function using hepa-tocytes (e. g. in haemofiltration systems or bioreactors) is conceivable in acute liver failure, possibly in conjunction with activated charcoal filtration or with plasma separation. The importance lies in bridging the phase of acute liver failure until compensation of the liver function or liver regeneration is achieved. 

Falkenhagen, D., Strobl, W., Vogt, G., Schrefl, A., Linsberger, L, Gerner, F.J., Schoenhofen, M. Fractionated plasma separation and adsorption system a novel system for blood purification to remove albumin bound substances. Artif Organs 1999 23 81-86... 

Ohashi K, Tashiro K, Kushiya F, Matsumoto T, Yoshida S, Endo M, Horio T, Ozawa K, and Sakai K, Rotation-induced Taylor Vortex enhances filtrate flux in plasma separation, ASAIO Trans. 1988 34(3) 300-307. 

The performance of intensive plasma exchange (removal from an adult of 2-3 liters of plasma with substitution of fresh plasma to maintain the patient s blood volume) requires separation of plasma from cells, so that the patient s own cells can be returned. There are two methods of plasma separation centrifugal flow separation and flow filtration (1,2). 

Schwenger V. Plasma separation in severe propafenone intoxication. Intensivmed Notf Med 2001 38 124-7. 

Albumin solution, human (PhEur 2005) Human albumin solution is an aqueous solution of protein obtained from plasma. Separation of the albumin is carried out under controlled conditions so that the final product contains not less than 95% albumin. Human albumin solution is prepared as a concentrated solution containing 150-250 g/L of total protein or as an isotonic solution containing 35-50 g/L of total protein. A suitable stabilizer against the effects of heat such as sodium caprylate (sodium octanoate) or N-acetyltryptophan or a combination of these two at a suitable concentration, may be added, but no antimicrobial preservative is added at any stage during preparation. The solution is passed through a bac-teria-retentive filter and distributed aseptically into sterile containers, which are then closed so as to prevent contamination. The solution in its final container is heated to 60 1.0°C and maintained at this temperature for not less than 10 hours. The containers are then incubated at 30-32°C for not less than 14 days or at 20-25°C for not less than 4 weeks and examined visually for evidence of microbial contamination. 

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