• Journal of the Korean Electrochemical Society
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• v.12 no.4
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• pp.335-341
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• 2009

Organic-inorganic hybrid sol-gel matrices were used as hosts for chloro (5, 10, 15, 20-tetraphenylporphyrinato) cobalt (III) (Co[TPP]Cl), a known ionophore for nitrite. The sol-gel precursor was prepared by the reaction of (3-isocyanopropyl) triethoxysilane with 1,4-butanediol. An appropriate amount of the anion-exchanger, tridodecylmethylammonium chloride (TDMAC) and the plasticizer, tributylphosphate (DBP) were used as membrane additives. On mixing with an acidic catalyst, the sol-state precursors slowly gelled, yielding a membrane in which the active components, Co[TPP]Cl and TDMAC, were encapsulated. The performances of the sol-gel membrane-based electrodes were compared to those of Co[TPP]Cl-based poly(vinyl chloride) (PVC) membrane electrodes. Membranes with a molar ratio of Co[TPP]Cl: TDMAC (1 : 0.1) showed reasonable response slopes toward nitrite. The response slopes were typically 53 mV/decade between $10^{-5.4}$ and $10^{-1.0}\;M$. Selectivities toward nitrite over hydrophilic and small anions such as chloride were somewhat inferior to those observed with PVC-based membranes, but selectivities over lipophilic anions were quite similar. Reduced asymmetry potentials due to protein adsorption were found to occur with the sol-gel matrix relative to PVC-based films when the sensors were employed as a detector in flow-through configuration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1584-1587
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• 2004

The betaine content of Saliconia herbacea L. was determined by reverse-phase high performance chromatog-raphy on a C_(18) column. A 50% methanol extract was passed through a anion exchanger Ambelite IRA 400 (quaternary ammonium type, OH-) column and a strong cation exchanger Ambelite IR 120 (sulfonic acid type, $H^+$) column to remove amino acids, zwitter ions which are interfere with betaine analysis. The betaine extract was derivatized with 18-crown-6-ether and 4-bromophenacyl bromide (PBPB) for UV-labelling. Betaine in Saliconia herbacea L. was analysed on a mobile phase contained 13 mM sodium heptane sulfonic acid and 5 mM $Na_2SO_4$ in deionized water by isocratic elution for 30 min. The recovery ratio of betaine from Saliconia herbacea L. extract was 83.6%. The mean betaine value for Saliconia herbacea L. determined by the described method is 4.85 mg/mL with a standard deviation of 0.127.

• Polymer(Korea)
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• v.26 no.2
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• pp.160-167
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• 2002

We synthesized HPP-g-GMA copolymer using pre-irradiation method by E-beam and aminated HPP-g-GMA using amination reaction. Degree of grafting increased with increasing GMA monomer concentration and showed the maximum value of 130% at 1.46 M of GMA. The degree of amination increased with increasing the degree of grafting. When the degree of grafting was 100%, degree of amination showed the maximum value of 37.4%. The ion exchange capacity of aminated HPP-g-GMA was about 3.78 meq/g, and it showed remarkable adsorption ability of hollow fiber ion exchanger. Through the BET analysis, the surface area of aminated HPP-g-GMA was 54.83 $\m^2/g$ and the mean pore size was $26\AA$. These showed the decrease of surface area and the slight increase of the mean pore size. SEM results show that the thickness of fiber increased after the step of reaction and there pore blocking phenomena was not observed. The aminated HPP-g-GMA was synthesized successfully and found to be suitable for the adsorption and separation of anion.

• Analytical Science and Technology
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• v.10 no.1
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• pp.53-59
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• 1997

Chloride form anion exchange resin was used to separate one of the elements from the rare earth mixture using respectable Ln-EDTA eluent. $Sm^{3+}$, $La^{3+}$ or $Ce^{4+}$ complexed with EDTA was passed through the resin column and eluted with a Sm-EDTA solution as an eluent. Here all the rare earth element ions except $Sm^{3+}$ were passed. Adsorbed $Sm^{3+}$ in resin was eluted with 1.0 M HCl solution. If La-EDTA solution as an eluent was used to separate lanthanum ions, lanthanum ions were eluted together with other rare earth elements. When Ce-EDTA solution was also used for separation of $Ce^{4+}$, it was eluted in the region of other rare earth elements. In the case of Sm-EDTA elution, the elution mechanism was as follows : Absorption : $RCl+Ln-Y^-{\leftrightarrows}RLnY+Cl^-$, Sm-EDTA elution : $RLnY+Sm-Y^-{\leftrightarrows}RSmY+Ln-Y^-$, HCl elution : $RSmY+HCl{\leftrightarrows}RCl+Sm-Y^-$.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.2
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• pp.91-95
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• 2012

The role of the kidney in combating metabolic acidosis has been a subject of considerable interest for many years. The present study was aimed to determine whether there is an altered regulation of renal acid base transporters in acute and chronic acid loading. Male Sprague-Dawley rats were used. Metabolic acidosis was induced by administration of $NH_4Cl$ for 2 days (acute) and for 7days (chronic). The serum and urinary pH and bicarbonate were measured. The protein expression of renal acid base transporters [type 3 $Na^+/H^+$ exchanger (NHE3), type 1 $Na^+/{HCO_3}^-$ cotransporter (NBC1), Na-$K^+$ ATPase, $H^+$-ATPase, anion exchanger-1 (AE-1)] was measured by semiquantitative immunoblotting. Serum bicarbonate and pH were decreased in acute acid loading rats compared with controls. Accordingly, urinary pH decreased. The protein expression of NHE3, $H^+$-ATPase, AE-1 and NBC1 was not changed. In chronic acid loading rats, serum bicarbonate and pH were not changed, while urinary pH was decreased compared with controls. The protein expression of NHE3, $H^+$-ATPase was increased in the renal cortex of chronic acid loading rats. These results suggest that unaltered expression of acid transporters combined with acute acid loading may contribute to the development of acidosis. The subsequent increased expression of NHE3, $H^+$-ATPase in the kidney may play a role in promoting acid excretion in the later stage of acid loading, which counteract the development of metabolic acidosis.

• Polymer(Korea)
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• v.33 no.1
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• pp.72-78
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• 2009

In this study, the behaviour of $SO_2$ and $NO_2$ adsorption on aminated ultrafine fibrous PP-g-AAc ion exchanger was investigated, The amount of adsorbed $SO_2$ increased with increasing the initial concentration of $SO_2$. The adsorption breakthrough time in the low concentration of $SO_2$ was faster than high concentration. The adsorption breakthrough occurred within 60 min. Approximately 80% of $SO_2$ was adsorbed below 100 ppm $SO_2$ and 90% of $SO_2$ over 100 ppm $SO_2$ respectively. The selective adsorption rate for $NO_2$ was lower than that of $SO_2$. The adsorption rate for $SO_2$ was decreased with increasing flow rate and that of $NO_2$ was 60%. The breakthrough occurred within 60 min. The adsorption rate for $SO_2$ was 92% in the 250 mL/g water content. Isotherm adsorption model for $SO_2$ was close to the Langmuir rather than Freundlich model.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.1 no.2
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• pp.214-220
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• 1991

As chromium in urine remains as oxychromic acid ions, chromium was extracted by using ion pair formed by anion exchanger trioctylamine. then after it is noted whether this TOA-MIBK method is effective or not for the chromium analysis by using flame method of Atomic absorption Spectrophotometric Analysis. The result is as following. 1. Effects of various acids on the extraction of Cr with MIBK including TOA are good in order $NHO_3$, $H_2SO_4$, HCl in distilled water sample and its proper concentration of HCl is 0.2 N. 2. For the analysis of urine sample, the best result can be achieved by following condition. After finished pretreatment adjusted to pH 6.5-7.5 by NaOH and again controlled pH 0.5-0.6 by HCl. 3. Though TOA concentration slightly affects the analytic value, best result is noted in 1-3% concentration. 4. Recovery rates of urine samples made by $0.3mg/l{\cdot}urine$, $0.6mg/l{\cdot}urine$, $0.9mg/l{\cdot}urine$ are shown from 96.7% to 104.8%. 5. Recovery rates of urine samples made by $0.01mg/l{\cdot}urine$, $10.03mg/{\cdot}urine$, $0.05mg/l{\cdot}urine$ are shown from 89.3% to 98.6%.

• BMB Reports
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• v.34 no.4
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• pp.310-315
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• 2001

The uneven distribution of acidic and basic chitinases in different parts of rice seed, and also the characterization of hull-specific chitinases, are reported here. After extraction of chitinases from polished rice, bran, and rice hulls, the chitinases were separated into acidic and basic fractions, according to their behavior on an anion exchanger column. Both fractions from different parts of rice seed showed characteristic activity bands on SDS-PAGE that contained 0.01% glycol chitin. The basic chitinases from rice hulls were further purified using chitin affinity chromatography. The chitinase, specific to rice hulls (RHBC), was 88-fold purified with a 1.3% yield. RHBC has an apparent molecular weight of 22.2 kDa on SDS-PAGE. The optimal pH and temperature were 4.0 and $35^{\circ}C$, respectively. With [$^3H$]chitin as a substrate, RHBC has $V_{max}$ of 13.51 mg/mg protein/hr and $K_m$ of 1.36 mg/ml. This enzyme was an endochitinase devoid of ${\beta}$-1,3-glucanase, lysozyme, and chitosanase activities.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.117-120
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• 2014

Several studies have reported that the citrus red mites Panonychus citri were an important allergen of citrus-cultivating farmers in Jeju Island. The aim of the present study was to purify and assess properties of a cysteine protease from the mites acting as a potentially pathogenic factor to citrus-cultivating farmers. A cysteine protease was purified using column chromatography of Mono Q anion exchanger and Superdex 200 HR gel filtration. It was estimated to be 46 kDa by gel filtration column chromatography and consisted of 2 polypeptides, at least. Cysteine protease inhibitors, such as trans poxy-succinyl-L-leucyl-amido (4-guanidino) butane (E-64) and iodoacetic acid (IAA) totally inhibited the enzyme activities, whereas serine or metalloprotease inhibitors did not affect the activities. In addition, the purified enzyme degraded human IgG, collagen, and fibronectin, but not egg albumin. From these results, the cysteine protease of the mites might be involved in the pathogenesis such as tissue destruction and penetration instead of nutrient digestion.

• Parasites, Hosts and Diseases
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• v.46 no.3
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• pp.183-186
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• 2008

Helminthic cysteine proteases are well known to play critical roles in tissue invasion, nutrient uptake, and immune evasion of the parasites. In the same manner, the sparganum, the plerocercoid of Spirometra mansoni, is also known to secrete a large amount of cysteine proteases. However, cysteine protease inhibitors regulating the proteolytic activities of the cysteine protease are poorly illustrated. In this regard, we partially purified an endogenous cysteine protease inhibitor from spargana and characterized its biochemical properties. The cysteine protease inhibitor was purified by sequential chromatographies using Resource Q anion exchanger and Superdex 200 HR gel filtration from crude extracts of spargana. The molecular weight of the purified protein was estimated to be about 11 kD on SDS-PAGE. It was able to inhibit papain and 27 kDa cysteine protease of spargana with the ratio of 25.7% and 49.1%, respectively, while did not inhibit chymotrypsin. This finding suggests that the cysteine protease inhibitor of spargana may be involved in regulation of endogenous cysteine proteases of the parasite, rather than interact with cysteine proteases from their hosts.