摘要:

AbstractRheoelectrolysis is defined as convection‐free electrolysis of an electrolytic solution under simultaneous liquid transport from anolyte to catholyte andvice versa. Equal rate of transfer in both directions is assumed in this paper, and hence there is no liquid flow within the electrolyser. If this process is conducted long enough, a steady state can be expected, characterised by mutually balancing flows of ion constituents within the electrolyser (by electric migration) and in external ducts (by pumps). The differential equation of the steady state is deduced, and it is shown that it is easily solvable if transport numbers and diffusion coefficients are constant throughout the electrolyser. In this case the concentration courses become linear. The conditions for the presence of both buffer components in all parts of the electrolyser. are given. These conditions being satisfied, it is possible to calculate the pH course to be expected throug the eleltolyer. It is found that a pH span of about 2.6 unite can be covered by the rheoelectolysis of an odinary buffer solution. The pH gradient is at a minimum at the centre of the apparatus and increases towards both electrodes. The pH courses is sigmoid in shape and appears to be very useful for isoelectric focusing of proteins and other ampholytes. The method may become important in preparative work on a large scale in order to save the cost of carrier ampholytes in quantitie

ISSN:0173-0835    

DOI:10.1002/elps.1150020502

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractSteady‐state rheoelectrolysis of a salt of a weak base and a weak acid, with a possible excess of base or acid, is treated theoretically. For an accurate deduction of the pH course through the region where the pure salt prevails, the treatment is based directly on the mass action equations and not on Henderson's equation. However, the conductivity contributions of the water ions H+and OH−are not taken into account, a limitation that restricts the validity of the theory roughly to the pH region between 4 and 10. The pH span that can be covered by this technique is found to be about 2.5 units bigger than the pK difference between base and acid. An exact expression for the pH gradient is deduced, and it is shown that this gradient has a maximum at the location of the pure salt and minima in the neighbourhood of the two pK values. There is no theroretical obstacle to the use of this technique for isoelectric focusing without carrier ampholy

ISSN:0173-0835    

DOI:10.1002/elps.1150020503

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractIt was recently observed that bovine serum albumin (BSA), adsorbed onto part of the surface of a glass slide, diffuses along the unoccupied part of that surface (without redissolving in the bulk liquid) at a much greater velocity than the normal diffusion rate of BSA, free solution. In this work a study is made of the electrophoretic transphoretic transport of BSA, adsorbed onto part of the surface of glass slide, along the hitherto unoccupied part of the glass surface. The electrophoretic mobility of adsorbed BSA along the unoccupied glass surface proved to be up to ≅ 2 times faster than in electrophoresis on cellulose acetate strips at the same pH and ionic strength, and up to ≅ 1.6 times faster than in moving boundary electorphoresis. The increase in electrophoretic mobility of adsorbed BSA is most pronounced at the highest density of adsorption. At that density the oblong BSA molecules are closely packed, most probably adsorbed in a tight monolayer, with each molecule positioned perpendicular to the glass surface (although other configurations cannot be excluded). The major driving force enhancing the diffusivity, as well as the electrophoretic mobility of adsorbed BSA, appears to be the high surface pressure of he tightly packed BSA layer. A tentative explanation is offered for the low resistance BSA molecules encounter in moving parallel to the glass surface while remaining adsorbed to the liquid, involving free energies of adhesion of individual protein molecules in various orientati

ISSN:0173-0835    

DOI:10.1002/elps.1150020504

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractThe analysis of immunoglobulin by gel electrophoretic methods is presently burdened with two problems: the incapacity of conventional buffer systems to spread the polyclonal immunoglobulin pattern across the entire separation path length in gel electrophoresis, and the appearance of distinct bands in the conventional electrofocusing patterns, instead of he continuum of zones — which would be expected form a polyclonal mixture of “charge isomers” and which is indeed obtained in gel electrophoresis. Polyclonal serum immunoglobulin differ from one another predominantly in net charge (i.e., they are “charge isomers”). The operative pH of gel electrophoresis was therefore optimized. The acidic side of he isoelectric operative pH of 5.32, a discontinuous (multiphase) buffer system was found which was capable of stacking all immunoglobulin in a lyophilized preparation.In order to provide a magnified view immunoglobulin heterogeneity, the immunoglobulin mixture was fractionated into 26 groups of charge isomers using preparative isotachophoresis. When subjected to polyacrylamide gel electrophoresis in resolving gels operative at pH 4.85, 0°C, the isotachophoretic fractions spread between relative mobility values of 0.4 to 0.9 in the electrophoresis pattern,i.e., their sum total covered the entire separation path. Under these conditions, isotachophoretic fractions also revealed immunoglobulin oligomers. The number of oligomeric forms increased from increased from the leading (most basic) to the trailing (most acidic) immunoglobulin components within the stack.In polyacrylamide gel electrofocusing of the isotachophoretic fractions of immunoglobulin, using pI‐renge 6–9 ampholine, addition of a 0.01 M mixture of amino acids to the carrier ampholytes, and 20h or more electrofocusing time at 20 V/cm of gel, 0°C, polyclonal immunoglobulin patterns appeared continuous. Electrofocusing patterns of those isotachophoretic fractions of immunoglobulin which contained oilgomeric forms (as revealed by gel electrophoresis ) exhibited one or two major bands against the continuous background of stainable components. Monoclonal immunoglobulin produced distinct major bands under the same comditions.Thus, either polyacrylamide gel electrofocusing in the pI‐range 6–9 or polyacrylamide gel electrophoresis in a buffer system operative at pH 4.85 appear promising for the development of a clinically practical and artifact‐free electrophoresis analysis for specific oligo

ISSN:0173-0835    

DOI:10.1002/elps.1150020505

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractThe effect of voltage on the rate of desorption of radiolabeled rabbit immunoglobulin G (IgG) from protein A‐Sepharose was studied. In the absence of voltage, the rate of desorption was measured using a vast excess of unlabeled IgG to prevent re‐adsorption. Electrophoretic desorption was measured using a column equipped with electrodes and with eluent flow occurring in the direction of electrophoresis. The rate of desorption was very sensitive to voltage, and, furthermore, desorption could occur at a rate 25 times faster than in the absence of a voltage. The results are interpreted to indicate that the presence of voltage not only altered the equilibrium of the system but altered the equilibrium or rate constants of the sys

ISSN:0173-0835    

DOI:10.1002/elps.1150020506

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractThe kinetics of photopolymerization, in presence of riboflavin or riboflavin‐5′‐phosphate (FMN), have been studied either spectrophotometrically, at 283 nm, or chemically, by titrating unreacted double bonds with permanganate. The two sets of data are in good agreement and suggest that at least 8 h of light exposure are needed to ensure 95% conversion of monomers into polymers. Up to now, it was generally accepted that photopolymerization should proceed for 1 h. It is not necessary to prolong light exposure for longer than 8 h, because even a 24 h illuminatin period only improves the conversion from 95% to 96%. Although conditions are described which ensure at least 95% conversion of both riboflavin‐and persulfate‐catalyzed gels, their visco‐elastic properties are widely different, suggesting that the final structure of these two matrices must vary considerably as a function of the ca

ISSN:0173-0835    

DOI:10.1002/elps.1150020507

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractPeroxidase isozymes from two flax genotypes were separated electrophoretically using a range of concentration, regression models were fitted by weighted least squares method, using matrix techniques and appropriate programmes, weight were reciprocals of variances of significance, as a chi square, of the residual sums of square (SS). Log (Rm) Plotted against gel concentration showed significant curvilinearity; Log (P/Hb), where P was an isozyme's migration was linear with concentration. Matrix method allowed a completely generalized approach to the analysis of data of this type. In particular, regression data could be readily combined so as to allow orthogonal comparison between Intercepts and slops in an analohgous fashion to the orthogonal breakdown of row, column and interaction effects in a balance two‐way analysis of Weighting effected some improvement in comparison between isozymes; combined analyses of weighted regression produced striking improvement in discrimination relative to simple pairwise Comparisons between isozyme

ISSN:0173-0835    

DOI:10.1002/elps.1150020508

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractSix of the most recent silver staining method for detecting polypeptides on polyacrylamide gels were compared. We found the method of Sammonset al.(Electrophoresis, 1981, 2, 135–141) to be least expensive and most reproducible, For staining gels of 1.5 mm in thickness, it is also the most sensitive method. Other methods may be preferable for staining gels 0.8 mm or less in thicknes

ISSN:0173-0835    

DOI:10.1002/elps.1150020509

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractA simple method for the quantitative determination of glycosaminoglycan concentration and radioactive precursor incorporation into glycosaminoglycans is describe. Tissue glycosaminoglycans are separated by electrophoresis on cellulose acetate sheets. Sheets are then impregnated with diphenyloxazole in toluene and tritium activity quantitated by fluorography. Absolute absorbance measurement of X‐ray film fluorograms exposed for 80 h demonstrate a sensitivity of 50 dpm per samle (<5 dpm/mm2) and reproducibility of 7% Diphenyloxazole is removed with toluene and the sheets are stained with Alcian Blue. Absolute absorbance determination allow quantity measurement of mass with a sensitivity of 0.05 nmol of disaccharide subunit and a reproducibility of 6%. Beer's law is followed to 3nmol. Example of the utilization of this technique in studying radionuclide incorporation into glycosaminoglycans in these tissues‐ articuular cartilage, uterine cervix and skin‐are pres

ISSN:0173-0835    

DOI:10.1002/elps.1150020510

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractA new, simple procedure is described for the preparation gel matrix for preparativde isolelectic focusing (IEF). 0.5–1% Agarose of IEF grade is incorporated with 2.5% Sephadex G‐200 Superfine (SF) and 3% Pharmalyte, yielding a uniform and rifid m atirx. No gel washing, swelling of degassing is necessary. Optimum gel consistency is quickly and easily obtained since no dehydration of the gel timum gel consistency is quickly and easily obtained since no dehydration of the gel slurry is required. Gel preparation time is reduced to 0.5–1 h and gel handling is simplified. Protein can be easily recovered from the matrix. The pH gradient profile and resolving properties of agarose‐Sephadex were compared with those of Spphdex G200 SF and IEF‐grade agarose. The profiles of agarose‐Sephadex and Sephadex matrixes are smoother and extend further in both directions than those for agarose. Focusing in agarose‐Sephadex and Sephadex also results in fewer edge effects. The ability to distinguish closely resolved bands in agarose‐Sephadex is superior due to its ability to be directly stained and its avoidance of eletroen‐domestic effects associated with focusing in sgarose. Changes in voltages enables us to follow the development, stability, and decay of the pH gradient. Agarose‐Sephadex and Sephadex pH gradients developed more smoothly and remained more stable than those for agarose. This new support system combines the good focusing properties of Sephades G‐200 SF with the simple handling, rapid and uniform gel formation of agarose, while overcoming many of the drawbacks of using

ISSN:0173-0835    

DOI:10.1002/elps.1150020511

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY