Cellulose chromatography-modified

Trainor (1979) modified the above method (1) In the initial extraction, luciferin was extracted with 50 mM acetate buffer (pH 4.75) at 95°C, instead of boiling 20% methanol, to increase the extraction yield. (2) In the DEAE-cellulose chromatography, the column, on which the luciferin sample had been adsorbed, was washed with the following solvents before the elution of luciferin water, lOmM HC1 in methanol, methanol, and NaCl-saturated methanol. (3) To eliminate salts in purified luciferin, the solution was evaporated to dryness, and the luciferin in the residue was extracted with... 

In the following a slightly modified version of the conventional oligo(dT)-cellulose chromatography procedure suitable for obtaining poly-A+ RNA from about 1-10 mg total RNA is presented. 

Poly(ADP-ribose) modified proteins were isolated from E63 cells at different stages of myogenesis. Isolation and analysis of these proteins was performed essentially as described by Adamietz et al. [16] using boronate cellulose chromatography and per-... 

In addition to cellulose papers, modified-cellulose papers and glass-papers are also used for specific purposes. It is difficult to decide whether some self-supporting layers such as micropore membrane filter sheets or powders held in glass-paper sheets should be included among papers or thin layers. Paper chromatography is carried out in a descendant, ascendent or radial (circular) fashion. The diversity of the technique and the innumerable purposes to which it can be applied are discussed fully by textbooks and bibliographies, to which the reader is referred. 

Another technique employed to facilitate the chromatographic fractionation of casein involves the reduction and subsequent alkylation of the casein prior to chromatography (Rose et al. 1969 Yaguchi and Rose 1971 Davies and Law 1977). Rose et al. (1969) reduced whole casein with mercaptoethanol, alkylated the product with iodoacetamide, and separated the components on a DEAE-cellulose column (Figure 3.18). Davies and Law (1977) modified this procedure and achieved a quantitative estimation of the major caseins. 

Thin-tjayer Chromatography. Chiral stationary phases in tic have been primarily limited In phases based on normal nr inicrocrystalline cellulose, triaeelyleellulo.se sorbents or silica-based sorbents that have been chemically modified or physically coated to incorporate chiral selectors such as amino acids or macrocyclic antibiotics into the stationary phase. The cost of many chiral selectors, as well as the accessibility and success of chiral additives, may have inhibited widespread commercialization. 

Ap tamers can be selected in various ways. The most frequently used approaches are affinity chromatography [21] and modified cellulose filtration [4,22]. The choice of method depends on the properties of the target (for example, its capability to be immobilized on a matrix or to be bound to modified cellulose filters) and the aim of selection. If the desired aptamers should, for example, bind molecules on the surface of intact cells, the selection scheme should employ these cells adhering to the surfaces of tissue culture flasks [23]. 

The ultimate combination of HPLC and AC is effectuated in High Performance Affinity Chromatography (HPAC).47 The development of this hybrid technique was highly assisted by the use of modified silica. Traditional polysaccharide supports may not be used for HPAC, because they lack mechanical stability to withstand the high pressure drops, inherent to this method. Modified silica beads are well suited. These may be coated with active groups as in normal AC applications. Additionally, if the separation requires the use of an organic stationary phase, the silica beads are modified with a silane or polymer with subsequent deposition of polysaccharides such as dextrans, agarose or cellulose.50... 

The inherent chiral nature and availability of natural polymers, such as cellulose and amylose, were the primary reasons of their use in chiral separations. The ability of cellulose to separate racemic mixtures was first observed in paper chromatography [76,77]. The breakthrough point in the use of cellulose and amylose in modern HPLC was achieved with the development of CSPs where saccharides were adsorbed on the surface of aminopropyl-modified macroporous silica, [78,79]. 

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