Ion exchange papers

The possibility to use ion exchange papers like CM-, DEAE- and ECTEOLA-cel-lulose for electrophoretic separations was demonstrated by Yaron and Sober [38]. Huens and Jakubovic [39] used CM cellulose for the separation of haemoglobin variants. Several studies using paper impregnated with inorganic ion exchangers were reported. 

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At trace levels, polonium can be separated effectively by solvent extraction, ion exchange, paper chromatography, and other techniques. Diisopropyl ketone, di-n-octylamine, and tri-n-butylphosphate are suitable solvents for extraction. Trace amounts of polonium in solutions or sohd mixtures containing no other emitters can be determined by measuring its alpha activity. 

DE81 ion-exchange paper (Whatman) or TaKaRa Recochip (TakaraBio Inc.)... 

Cut a piece of DE81 ion-exchange paper the same width as the incision and slightly longer (2mm) than the gel s thickness. 

If desired, a TaKaRa Redochip can be used instead of the DE81 ion-exchange paper. In this case, the elution, extraction, and ethanol precipitation steps (steps 8-12 above) can be omitted. 

Fig. 3.4. Procedure for recovery of small DNA fragments with DEAE ion-exchange paper.

Lederer, M. Chromatography on Ion-Exchange Paper Inorganic Chemistry. Boll. Soc. Chim. France 1966, 16. 

The separation of water-soluble vitamins, including vitamin Bg, on ion-exchange paper has been described by Klotz and Huettenrauch, (101) using Amberlite SB-2, Amberlite WB-2, and Amberllte WA-2. 

Wheelwright, E. J. "Kilogram - Scale Purification of Americium by Ion Exchange," paper presented at Symposium on Separation Science and Technology for Energy Application,... 

Collins, E. D. Benker, D. E. Chattin, F. R. Ore, P. B. Ross, R. G., "Multigram Group Separation of Actinide and Lanthonide Elements by Li Cl-Based Ion Exchange", paper presented at Symposium on Industrial-Scale Production-Separation-Recovery of Transplutonium Elements, 2nd Chem. Congr. North American Continent, Las Vegas, NV, 1980. 

Another way of dealing with an excised zone is described by Adesnik (1970), and has been adapted to strips of gel cut from broad slabs on which are run as much as 5 mg of RNA (Adams et al. 1969). The gel slice is coarsely chopped up and placed into a cylindrical tube 10 x 1 cm, one end of which is covered with DEAE paper, and over this a layer of cellophane attached to the tube with a rubber band. The tube is filled with buffer (0.04 M Tris acetate, pH 8.3) and placed in a disc electrophoresis apparatus. After electrophoresis the RNA is found trapped in the ion-exchange paper, from which it is eluted as before. 

Fig. 9.1. Arrangement for elution of RNA from filter paper or ion-exchange paper. (In the latter case a high ionic-strength eluant would be used instead of water) (from Sanger and Tuppy, 1951.)...

Immunoassay Ion-exchange paper chromatography Isotopic methods Liquid chromatography... 

Brignal, W. J., A. K. Gupta, and M. Streat, The Theory and Practice of Ion Exchange (Paper 11) (London Society of Chemical Industry, 1976). 

Another modification in which form thin sheet electrophoresis is employed is known as ionophoresis. In this method, devised by Sanger and his co-workers, high voltage electrophoresis is carried out on ion-exchange paper. It is a rapid method of great resolution and sensitivity and is used in Biochemistry for the separation of constituents of a highly complex mixture e.g. a mixture of oligoribonucleotides produced by partial enzymic hydrolysis of RNA. For separation of the constituents of this hydrolysate mixture, a two-dimensional technique is used in which the mixture is subjected to electrophoresis on cellulose acetate and then the partially separated mixture is transferred to a DEAE-cellulose... 

Chemically reactive systems are those in which a special effect, in addition to partition and/or adsorption, lends added selectivity to the system. Examples include use of chemically modified cellulose (carboxyl paper), ion-exchange papers [34], or papers impregnated with a selective reagent (e.g., boric acid [35] for separation of various hydroxyl compounds), or the mobile phase may contain a reactive or complexing reagent in combination with normal or modified cellulose [21]. 

Equipment used for thin-layer electrophoresis is practically the same as that used for separations on paper, cellulose acetate and ion exchange papers. Usually cooling is introduced into the equipment. Thus, e.g., a water-cooled flat aluminium (dural, brass) block is insulated by means of a replaceable glass plate or plastic film. The thin-layer plate is located on the insulated block and paper wicks ensure the contact with electrode vessels. A polyethylene sheet is placed between the top of the layer and the lid. This protects the surface of the layer from drops of condensed moisture that condense on the lid. A sheet of plate glass covers the whole chamber. If precoated plastic thin-layer sheets are used, the apparatus of the immersed type can be used [78]. Elution of spots, and the general practice in thin-layer electrophoresis is the same as in thin-layer chromatography. 

GRI/LIB] Grimaldi, M., Liberti, A., Quantitative determination of the equilibria of copper, cobalt, nickel and cadmium ions in chloride solutions by means of ion-exchange papers, J. Chromatogr., 15, (1964), 510-513. Cited on pages 146, 147,311. 

In a more recent account Bergmann and co-workers adapted the use of sulfur as a reagent to reduce porphyrin loss during combustion, thus obviating iron contamination from benzene sulfonic acid. Also described was a procedure for the concentration of metals on a suitable disk of ion exchange paper. 

Ion exchange papers. A combination of the specificity of ion exchange with the convenience of paper chromatography is afforded by ion exchange papers. There are two kinds. One consists of cellulose where acidic groups have been introduced by chemical modification of the -OH groups, e.g. conversion to carboxylic, phosphoric and sulphonic acids and to A,A-dialkylamines. These papers are suitable for the separation of cations, amines and amino acids. 

To illustrate the use of ion exchange papers for the separation of metals. A strong and a weak acid cation exchange modified cellulose paper are used, in the form in which they are supplied. 

Note that the strong acid paper gives a better separation than the weak acid type. The order of elution on the ion exchange paper is opposite to that in normal chromatography (Figure 9.2). Notice also that on P81 paper the iron does not move, because of the high stability of the iron-phosphate complex. The approximate Rf values are given in Table 9.1. 

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