• 대한화학회지
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• 제41권11호
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• pp.612-638
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• 1997

모나자이트광 속에 포함되어 있는 회토류 원소들을 이온교환수지를 이용하여 분리 회수 하는 방법에 관해 연구하였다. 이온교환수지로는 양이온교환수지와 음이온교환수지를 사용하고, 용리액으로는 EDTA, DTPA, IMDA, Ln-EDTA 용액을 사용하였으며, 양이온교환수지는 retaining 이온 곧 $H^+, Zn^{2+}, Fe^{3+}, Al^{3+}, Cu^{2+}, NH^+_4$으로 치환된 수지를 사용하였다. 음이온교환수지는 EDTA로 치환된 수지에 Ln-EDTA착물을 흡착시켜 분리하였다. 여러 가지 회토류 원소 중에서 선택적으로 한 원소만 분리하기 위해 용리액으로 Ln-EDTA를 사용하였으며, 수지통의 크기 변화와 여러 가지 용리형태의 메카니즘, 그리고 다량의 회토류 원소를 분리 회수하는 방법 등에 관해 연구하였다.

• 대한화학회지
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• 제34권1호
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• pp.69-75
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• 1990

모자나이트 광물 중에 포함된 각각 희토류 원소를 이온회합 크로마토그래피 방법으로 분리 및 정량하였다. 정량하기 전에 양이온교환수지(Dowex 5OW-X8) 칼럼으로 희토류 원소를 집단 분리하였다. 이 때 수지 칼럼에 의하여 희토류 원소가 정량적으로 회수되며, 시료 중의 공존이온으로부터 깨끗이 분리됨을 방사성 추적자 및 유도쌍 결합 분광-질량분석법(ICP-MS)으로 각각 확인 하였다. 역상 칼럼($\mu$-Bondapak $C_{18}$)에 의하여 미량(ppm)의 희토류 원소를 pH 4.6의 $\alpha$-hydroxyisobutyric acid으로 0.05M부터 0.3M까지 기울기 용출하여 각각 분리하였다. 희토류 원소와 PAR (4-(2-pyridylazo)-resorcinol monosodium salt)과의 포스터 칼럼 착색반응을 통하여 각각의 희토류 원소를 검출하였다.

• KSBB Journal
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• 제23권1호
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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.

• 대한핵의학회지
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• 제7권1호
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• pp.51-54
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• 1973

The use of ion-exchange resins for the treatment of radioactive wastes has many advantages, but thes eare rather expensive as compared with the Korean vermiculite. The Korean vermiculite has slightly different chemical constituents from the ones produced in other countries, and its physical properties might be applicable to the management of radioactive waste, in a small nuclear installation. The decontaminating effect of Korean vermiculite for the low-level radioactive liquid was investigated. $^{106}Ru,\;^{90}Sr,\;and\;^{137}Cs$ were utilized for the experiments. The removal rates by Korean vermiculite were calculated for $^{106}Ru,\;^{90}Sr\;and\;^{137}Cs$ and the removal rates increased as the weight of vermiculite in the exchange column increased. The decontaminating constants, $K_d$ of the Korean vermiculite for $^{106}Ru,\;^{90}Sr\;and\;^{137}Cs$ were 2.7, 69.3 and 263ml/g respectively. Through the results of experiments, the application of Korean vermiculite column to the treatment of low-level radioactive waste is quite feasible.

• FOCUS: LIFE SCIENCE
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• 제1호
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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.

• 상하수도학회지
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• 제33권2호
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• pp.131-140
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• 2019

This study used a packed column reactor and a horizontal flow mesh reactor to examine the removal of copper ions from aqueous solutions using pine bark, a natural adsorbent prepared from Korean red pine (Pinus densiflora). Both equilibrium and nonequilibrium adsorption experiments were conducted on copper ion concentrations of 10mg/L, and the removals of copper ions at equilibrium were close to 95%. Adsorption of copper ions could be well described by both the Langmuir and Freundlich adsorption isotherms. The bark was treated with nitric acid to enhance efficiency of copper removal, and sorption capacity was improved by about 48% at equilibrium; mechanisms such as ion exchange and chelation may have been involved in the sorption process. A pseudo second-order kinetic model described the kinetic behavior of the copper ion adsorption onto the bark. Regeneration with nitric acid resulted in extended use of spent bark in the packed column. The horizontal flow mesh reactor allowed approximately 80% removal efficiency, demonstrating its operational flexibility and the potential for its practical use as a bark filter reactor.

• 대한의생명과학회지
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• 제18권2호
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• pp.96-103
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• 2012

Kv 4.2 ion channel protein has an ability to open at subthreshold membrane potentials and to recover quickly from inactivation. That is very important for neuronal signal transmission in vertebrate brain. In order to purify Kv 4.2 protein, the novel purification methods were experimented. The purification procedure utilized chromatography on DE-52 ion exchange column and affinity chromatography on a WGA-Sepharose 4B, and Kv 4.2 affinity column chromatography. It was found that 0.5% (wt./vol.) Triton X-100 detergent in lysis buffer worked well for Kv 4.2 protein solubilization from rat brain membrane. Protein quantitative determination was conducted by BCA method at 562 nm for each purification step to avoid determination interference of protein at 280 nm by detergent. The confirmation of Kv 4.2 existence and amount is performed using by SDS-PAGE/immunoblotting or 96-well dot blotting. The Kv 4.2 without interacting protein that contains carbohydrate, was purified from novel biochemical 3-steps purification method for further research.

• 생약학회지
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• 제24권2호
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• pp.177-182
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• 1993

The pericarp of Cornus officinalis is well known famous medicinal drug in oriental countries. In this work, we have tried to evaluate the toxicity and also to find the lectin components from this seed. The lyophilized seed extract was lethal to experimental mouse at $250{\sim}300mg/kg$ and this toxic components were related to proteins. The lectins components were partially purified from the extract by ion exchange column chromatography. These lectins were relatively stable at temperature variations and also stable at pH $4{\sim}7$. The activity of these lectins did not inhibit by common carbohydrates molecules.

• Biomolecules & Therapeutics
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• 제6권4호
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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.

• 한국식품영양학회지
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• 제1권2호
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• pp.50-55
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• 1988

B-Amylase was obtained from sweet potato extract in a crystalline state by dialysis against water after precipitated with acetone according to the method reported previously followed by DEAE Sephadex A-50 ion exchange chromatography plus gel chromatography of Sephadex G-200. The purified enzyme was homogeneous by SDS PAGE. The efforts had done to remove the miner bands in SDS PAGE by Sephadex G-200 gel chromatography, DATE Sephadex A-50 ion exchange chromatography. isoelectrophocusing, affinity chromatography, hydroxyapatite chromatography, recrystallizstion and HPLC on a column of TSK gel SW 3000 but have given any result. But, N -terminal amino acid of the enzyme was revealed mainly alanine and trace of glycine and glutamic acid. Therefore, it seems that the miner bands in SDS PAGE have a role of subunit.