Free boundary electrophoresis

The unidimensional type of paper electrophoresis is an extension of free boundary electrophoresis, the method developed by Tiselius (Tl). There are several differences between the two systems. One is the presence of a substrate (supporting medium) as anticonvectional medium during the electrophoretic separation. Another important difference is the starting point. In paper electrophoresis the entire load of material due to be separated is collected on the starting line, whereas in free boundary electrophoresis the material is present in equal concentration over one leg of the electrophoretic cell. Fortunately these differences simplify the qualitative and quantitative appraisal of separation after the run on paper, and for practical work both prove to be true inherent qualities and go far to account for the success of the method (Kl, VI, Wl). 

Taylor was unable to separate catheptic from peptic activity, either by ammonium sulfate and sodium chloride precipitation, or by ion-exchange chromatography, free boundary electrophoresis (Fig. 2), or differential ultracentrifugation (T24, T26). 

Mack et al. (MI, Mia) extended this work and subjected human gastric juice to free boundary electrophoresis in an analytical Aminco... 

Two protease fractions were observed by Herriott (see G5) on free boundary electrophoresis of crystalline swine pepsin, and two proteases were separated by Merten et al. from hog gastric extracts (M4), as well as by Taylor from human gastric juice (T6). Like pepsin, both moved to the anode at pH 2.5. 

Grossberg et al. (G32), using free boundary electrophoresis, found peptic activity distributed through practically all 5 electrophoretic components of acid canine gastric juice. However, this is not so with zone electrophoresis of human gastric juice (see below). 

Pugh et al. (P7) and Mack et al. (Mia, M2), using free boundary electrophoresis, showed that mucoprotein and mucoproteose fractions of the dissolved mucin (G5) had different electrophoretic mobilities mucoprotein fast anodic mobility (5.5-6.9 X cm sec volts ), mucoproteose slow anodic mobility (0.5-1.0 X cm sec volts ) in veronal buffer of pH 9.2 (Fig. 1). Soluble mucus had intermediate mobility of — 3.5 X 10 . It was also noted by Mack et al. (Ml) that the mucoprotein fraction processed from the acid human gastric juice, when nm by itself on Tiselius electrophoresis or when added to acid gastric juice, did not have as fast mobility as the fastest anodic component of the gastric juice, which had a mobility of 7.4-7.S X cm sec volts and which probably, as we know now, corresponded to the complex of pepsin and mucoprotein (see G5). 

C. Stable-Flow-Free Boundary Electrophoresis (STAFLO)... 

C. STABLE-FLOW-FREE BOUNDARY ELECTROPHORESIS (STAFLO) ACCORDING TO MEL... 

Boundary anomalies can also occur in free-boundary electrophoresis, because mobility often depends on the concentration the effects can be large and it is difficult to apply corrections for them. 

Electrophoretic separation techniques involve a good deal of instrumentation and also involve free-boundary electrophoresis, zone electrophoresis on celluloses acrylamide, and so forth, as well as isoelectric focusing techniques. 

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