Globulins, plasma separation

A method for the fractionation of plasma, allowing albumin, y-globulin, and fibrinogen to become available for clinical use, was developed during World War II (see also Fractionation, blood-plasma fractionation). A stainless steel blood cell separation bowl, developed in the early 1950s, was the earhest blood cell separator. A disposable polycarbonate version of the separation device, now known as the Haemonetics Latham bowl for its inventor, was first used to collect platelets from a blood donor in 1971. Another cell separation rotor was developed to faciUtate white cell collections. This donut-shaped rotor has evolved to the advanced separation chamber of the COBE Spectra apheresis machine. 

Electrophoretic studies (G2, M2) have shown that both types of bilirubin are bound to albumin and sometimes a-globulin. Klatskin and Bungards (K6) found that this binding occurs between pH 6 and pH 9 and that below pH 5 separation occurs almost completely with respect to bilirubin but only partially with the conjugated pigment. This suggests that bilirubin and conjugated bilirubin are attached in different ways to plasma proteins. 

In a follow-up study, the same authors examined the applicability of the same device for relevant protein samples and investigated the main contributions to band broadening [82]. As a consequence of the small depth of the beds, zone spreading caused by Joule heating was shown to be negligible (see Sect. 3.1.1). Cross fields of up to 100 V/cm were applied for the separation of human serum albumin, ribonuclease A and bradykinin. The feasibility of fraction collection was demonstrated with four collected fractions of a whole rat plasma sample. Off-line analysis of these four isolated fractions by CE indicated the separation of serum albumins and globulins. 

After 4 1/2 hours 1.0 ml. blood contained 1.0 x 105 counts/min. Electrophoretic separation of plasma showed 77% of Cu associated with albumin fractions, 1 to 3% in each a-globulin fraction (total 10%), 1 to 3% in each -globulin fraction (total 10%), and about 3% in y-globulins... 

The most commonly biopolymers separated by Fl-FFF are proteins [49]. Fl-FFF is capable of separating proteins differing by just 15% in size within 3 to 10 min. S-Fl-FFF has been applied to a variety of proteins, including albumin, ovalbumin, y-globulin, hemoglobin, ferritin, lysozyme, [1-casein, apoferritin, human and rat blood plasmas and elastin [41,240,247]. Fl-FFF was also used to investigate the structural transformations of proteins [240]. 

Described in this section are different ways of determining albumin previously isolated (Sections 2.1 to 2.5) from not more than 200 1 whole plasma. Newer direct procedures for albumin and globulins which do not require prior separation of the proteins are also given. 

Electrophoretically separated bands of abnormal plasma proteins possess abnormal and variable lissamine green-binding capacities (B23). Part of the explanation for this lies in the heterogeneity of these fractions. Electrophoretically separated albumin is no exception and may be contaminated with lipid and lipoprotein on paper (03) and with lipid and an o-globulin on starch gel (P13). 

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