• Macromolecular Research
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• v.13 no.1
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• pp.39-44
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• 2005

Ion-exchange polymeric stationary phases presenting amino acid and amino groups were prepared by the surface grafting of glycidyl methacrylate onto a silica gel surface and subsequent amination. Three kinds of amino acids-L-arginine (Arg), D-lysine (Lys), and D-histine (His)-were used in this study. An ion-exchange polymeric stationary phase presenting ethylene diamine (EDA) was also prepared by surface graft polymerization. Separation of the model proteins bovine serum albumin (BSA), chick egg albumin (CEA), and hemoglobin (Hb) was performed using the amino acid- and amine-derived columns. In separating the CEA/BSA mixture, the resolution time of BSA was longer than that of CEA when using the EDA column, whereas the resolution time of BSA was shorter than that of CEA when using the Arg, Lys, and His columns. In the separation of the Hb/BSA mixture, the resolution time of BSA was longer than that of Hb in the EDA column, whereas the resolution time of BSA was shorter than that of Hb in the amino acid columns (D-Lys, L-Arg, and D-His).

• FOCUS: LIFE SCIENCE
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• no.1
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• pp.5.1-5.3
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• 2024

The document discusses the regeneration of Partisil/Partisphere ion-exchange columns in chromatography. It mentions that column efficiency can diminish with use due to the accumulation of sample and/or mobile phase impurities at the head of the column. This can lead to a change in back pressure, lower column efficiency, and sometimes a change in selectivity. The document outlines a procedure that may restore column performance. The document also provides everyday practices to enhance the lifetime of a column. These include using only high-purity HPLC solvents and buffers, using freshly prepared mobile phases and buffers, filtering mobile phases to remove particulates, using appropriate sample clean-up procedures, using a guard column or pre-column filter, and working within the pressure and flow rate limitations of the column. For the regeneration of Partisil/Partisphere SAX, SCX, WAX, and WCX columns, the document suggests passing 20 column volumes of various mobile phases through the column. These include a buffer wash, distilled water, an acid wash, a chelating wash, a methanol wash, and a buffer for separation. The document emphasizes that not all of these wash steps are required for every column clean-up and that some chromatographers require only a combination of certain steps.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2201-2206
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• 2010

To improve the separation property and stability of metal chelate Cu(II) column, three new kinds of multidentate aminocarboxy silica columns with cation-exchange properties were synthesized using glutamic acid (Glu), glutamic acidbromoacetic acid (Glu-BAA), glutamic acid-bromosuccinic acid (Glu-BSUA) as ligands and silica gel as matrix. The standard proteins were separated with prepared chromatographic columns. The stationary phases exhibited the metal chelate property after fixing copper ion (II) on the synthesized multidentate ligand silica columns. The binding capacity of immobilized metal ion was related with the dentate number of multidentate ligands. Chromatographic behavior of proteins and the leakage of immobilized metal ion on multidentate chelate Cu(II) columns were affected by the dentate number of multidentate ligands and competitive elution system directly. The results showed that quinquedentate Glu-BSUA-Cu(II) column exhibited better chromatographic property and stability as compared with tridentate Glu-Cu(II) column, tetradentate Glu-BAA-Cu(II) column and commonly used IDA-Cu(II) column.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.445-455
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• 2003

Relatively high carbon-14 emissions, which occurred at PHWR Plant during 1998 and 1999, made the site staff to implement several operational improvements: 1) the frequency and volume of the moderator cover gas purging were reduced through increased $O_2$ additions to the cover gas, 2) the 'old' resin columns were not used during re-start of the reactor from outage, 3) efforts were made to minimize air ingress, 4) the maximum service time of moderator ion-exchange columns were restricted to about 80 days. Through the improvements, the carbon-14 emission from each PHWR reactor returned to the normal levels during the remainder of 1999 and during 2000. We carried out a special surveillance at W-1 and W-3 from September 2001 to August 2002 to properly evaluate ways to optimize the use of moderator ion exchange resins from a C-14 perspective. The surveillance showed that only data that provided an operational marker for deciding when to remove the IX-resin column is an observed increase in the C-14 stack emissions themselves. Also, it is shown that any increase over the rate of 0.4 Ci $month^{-1}$ for two consecutive weeks may be the indication for an ion-exchange resin column change, especially if the IX-resin column has been in service for more than 80 days.

• FOCUS: LIFE SCIENCE
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• no.1
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• pp.1.1-1.4
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• 2024

This article provides comprehensive guidance on the maintenance, cleaning, regeneration, and storage of silica-based HPLC (High-Performance Liquid Chromatography) columns. The general considerations emphasize the importance of using in-line filters and guard cartridges to protect columns from blockage and irreversible sample adsorption. While these measures help, contamination by strongly adsorbed sample components can still occur over time, leading to an increase in back pressure, loss of efficiency, and other issues. To maximize column lifetime, especially with UHPLC (Ultra-High Performance Liquid Chromatography) columns, it is advisable to use ultra-pure solvents, freshly prepared aqueous mobile phases, and to filter all samples, standards, and mobile phases. Additionally, an in-line filter system and sample clean-up on dirty samples are recommended. However, in cases of irreversible compound adsorption or column voiding, regeneration may not be possible. The document also provides specific recommendations for column cleaning procedures, including the flushing procedures for various types of columns such as reversed phase, unbonded silica, bonded normal phase, anion exchange, cation exchange, and size exclusion columns for proteins. The flushing procedures involve using specific solvents in a series to clean and regenerate the columns. It is emphasized that the flow rate during flushing should not exceed the specified limit for the particular column, and the last solvent used should be compatible with the mobile phase. Furthermore, the article outlines the storage conditions for silica based HPLC columns, highlighting the impact of storage conditions on the column's lifetime. It is recommended to flush all buffers, salts, and ion-pairing reagents from the column before storage. The storage solvent should ideally match the one used in the initial column test chromatogram provided by the manufacturer, and column end plugs should be fitted to prevent solvent evaporation and drying out of the packing bed.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.659-665
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• 2012

IgY (Immunoglobulin Yolk) in egg yolk corresponds to IgG (Immunoglobulin G) in animal serum and plays an important role as immunological proteins in intestines. Carrageenan and Arabic gum were used as pretreatment agents to purify IgY from fresh egg yolk. DEAE (Diethylaminoethyl) Sepharose column in FPLC (Fast Protein Liquid chromatography) was an ion exchange tool to remove contaminants as well as to elute IgY from the column. GF HPLC (Gel Filtration High Performance Liquid Chromatography) enables to measure the molecular weights of IgY and to identify the purified IgY by comparing the molecular weight of standard IgY with the purified one. IgY is a heterogeneous group of different molecular weight and ionic properties, which was investigated with various IE HPLC (Ion Exchange High Performance Liquid Chromatography) columns such as AX, CX and SCX. Three peaks of IgY were separated in the AX column under the conditions of 0.5 M NaCl and pH=8. The SCX column also gave the three peaks of IgY at 0.5 M NaCl and pH=5.

• KSBB Journal
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• v.23 no.1
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• pp.31-36
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• 2008

The use of L-carbohydrates and their corresponding nucleosides in medicinal application has greatly increased. For example L-ribose has been much in demand as the starting material for curing hepatitis B. High performance liquid chromatography (HPLC) method was studied for the analysis of ribose and arabinose fractions from ion exchange chromatography (IEC). Dowex Monosphere 99 Ca/320 resin was packed in IEC to separate ribose and arabinose under various operating conditions. $NH_{2}$ and sugar HPLC columns were then used to analyze the fractions from the IEC column. Pulse input method (PIM) was also used to measure adsorption isotherms of ribose and arabinose in the Dowex column and HPLC columns. Experimental results and simulations by ASPEN chromatography were compared with fair agreement.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.616-618
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• 1992

The study was attempted to isolate taurine from the oyster shucking juice known as one of the by-products of oyster processing using ion exchange column chromatography. Three hundred grams of the oyster shucking juice were loaded onto a column packed with 300 ml of the Dowex 50W $H^+$ form. And taurine-rich fractions were further purified in columns packed with 150 ml of Dowex 2 OH form and the 150 ml of Amberite IRA-410 OH form consecutively. The purity and the yield of taurine recovered from the oyster shucking juice by this method were 94.7% and 84.8%, respectively.

• Biomolecules & Therapeutics
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• v.6 no.4
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• pp.364-370
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• 1998

Glycosidase inhibitors from urine of Bombyx mori were isolated and their inhibitory activities on glycosidases were evaluated. Six compounds were isolated by using several ion exchange columns, and their chemical structures were identified by the physicochemical and spectral data. Compound IV, V and Ⅵ were identified as 1-deoxynojirimycin, fagomine and 1,4-dideoxy-1,4-imino-D-arabinitol, respectively. Among six compounds isolated,1-deoxynojirimycin(IV) was the most potent inhibitor on $\alpha$-glucosidase and $\beta$-galactosidase of rat intestine, and its inhibitory activities for trehalase and almond $\beta$-glucosidase were relatively weak. Compound V and Ⅵl retained a little inhibitory potency toward $\alpha$-glucosidase and $\beta$-galactosidase. Compound II and III, however, have been found to have no effect on all glycosidases tested in this study.

• Fibers and Polymers
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• v.7 no.2
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• pp.112-116
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• 2006

Caprolactam is the most important raw material for making Nylon 6 fibers and its quality directly determines the quality of Nylon. So it is necessary to study the techniques and methods to remove the colorful impurities from caprolactam. In this paper, the decolorization of caprolactam aqueous solution by anion exchange resins was studied and the decoloring abilities of five commercial resins were investigated. The regeneration of the resins was also studied, too. This study shows that the resin AMTX202 have excellent decoloring ability in the column experiment and that the decoloring efficiency is correlated with the volume of resins packed and is slightly affected by the flow rate and regenerating times. The fact that the resins can be regenerated and reused without affecting the efficiency of decolorization will decrease the cost of the treatment and operation in the industry. The adsorption of colored compounds with anion exchange resins in the packed columns seems to be technically feasible.