Gel Exclusion Chromatography

Column chromatography Gel exclusion chromatography Ion exchange chromatography... 

Gel permeation chromatography, exclusion chromatography. gel filtration chromatography. A technique for separating the components of a mixture according to molecular volume differences. A porous solid phase (a polymer, molecular sieve) is used which can physically entrap small molecules in the pores whilst large molecules pass down the column more rapidly. A solvent pressure up to 1000 psi may be used. 

The packing material for liquid chromatography is produced from styrene and divinylbenzene dissolved in 50 to 300% by weight of organic solvent to both monomers. The constitution of divinylbenzene in the monomer mixture is not less than 60% by weight. In gel-permeation chromatography, the exclusive molecular weight is not less than 1 X 10 in terms of standard polystyrene (79). 

ASTM D-3536-91, Standard Test Method for Molecular Weight Averages and Molecular Weight Distribution by Liquid Exclusion Chromatography (Gel Permeation Chromatography-GPC), ASTM Annual Books of ASTM Standards, Vol. 08.02, P. 349—359. This method was deleted in the 1997 edition of the ASTM book. 

Dubin, P. L. and Principi, J. M., Hydrophobic parameter for aqueous size exclusion chromatography gels, Anal. Chem., 61, 780, 1989. 

Wyatt, P. J., Hicks, D. L., Jackson, C., and Wyatt, G. K., Absolute gel permeation chromatographic determination of molecular weight and sizes. Part 2. Incorporation of gel permeation chromatography-size exclusion chromatographic measurements, Am. Lab., 20, 108, 1988. 

PL Dubin, JM Principi. Hydrophobicity parameter of aqueous size exclusion chromatography gels. Anal Chem 61 780-781, 1989. 

The monodispersed nature of dendrimers has been verified extensively by mass spectroscopy, size exclusion chromatography, gel electrophoresis and electron microscopy (TEM). As is always the case, the level of monodispersity is determined by the skill of the synthetic chemist, as well as the isolation/purification methods utilized. 

Kessel D, Thompson P (1987) Purification and analysis of hematoporphyrin and hematoporphyrin derivative by gel exclusion and reverse-phase chromatography. Photochem Photobiol 46 1023-1025. 

We foimd that the ratiometric method is superior because it is not dependent on pyranine concentration and therefore free of error in pipeting (18,22,54). Calibration curves were constructed by preparing liposomes in which the hydration of the lipids to form MLV was done using solutions of high concentration at the desired pH in the range of 3.0 to 10.0. Gel-exclusion chromatography on a Sephadex column, as mentioned above, yielded a series of liposome preparations with a fixed external pH (pH 7.5), but different internal pH values determined by the buffer used for lipid hydration. Neither KI nor DPX, which quench the fluorescence of aqueous solutions of pyranine, has much effect on the fluorescence intensity of pyranine in the void volume after gel-exclusion chromatography, which indicates the complete removal of the pyranine from the extraliposomal medium. 

Y = ratio between [ C]-methylamine counts (dpm) and phospholipid concentration (mM) in the void volume fraction after the separation by gel-exclusion chromatography. Percentage of encapsulation (%) = Y/Xx 100. 

Figure 2 (right). Reverse-phase HPLC elution profile of the tumor-localizing fraction of HPD isolated by non-aqueous gel exclusion chromatography. (B) Hydrolysis of this material in 50% aqueous THF containing IM HCl, at 37 °C for 24 hours. (C) After hydrolysis in IM NaOH, 50% aqueous THF under the same condition. The major porphyrins resulted are hematoporphyrin (HP), hydroxyvinyl deutero-porphyrin (HVD), and protoporphyrin (PP). 

Partial Purification of SA-GTase. Proteins extracted from oat roots Incubated for 20 h in salicylic acid were separated by salt precipitation and gel exclusion and anion exchange chromatography (Table IV). A 5 -fold purification of the SA-GTase was achieved with this... 

Hofsten and Lalasidis (15), however, reported that plasteins subjected to gel exclusion chromatography in 50X acetic acid showed no increase in molecular size over that of the reactants. Monti and dost (29) reached the same conclusion based on gel chromatography in DMSO and on analysis of a-amino nitrogen in plasteins. Hofsten and Lalasidis (15) noted that hydrophobic peptides showed unusual elution behavior on sephadex gels in water or dilute buffers, providing a possible explanation for differences in their results compared to those of Arai et al. 

Pallavicini et al. (16) utilized a-chymotrypsin immobilized on chitin to catalyze plastein formation from leaf protein hydrolyzates. When analyzed by gel exclusion chromatography, the products were comparable to those produced by soluble enzymes. Modification of Specific Functional Properties... 

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