Use Of Anion Exchange Resin Research Articles

Fluorescence measurement of intracellular pH on proximal tubule suspensions. The need for a BCECF sink.

BCECF is used for intracellular pH (pHi) measurement in microperfused tubules. In this case, the perfusate washes out all BCECF leaking from the cells away from the optical light path. We have explored the use of BCECF for pHi determination on suspensions of dog renal proximal tubules (Percoll). This raises specific problems due to the accumulation of BCECF in the extracellular compartment generated by desesterification of BCECF-AM during loading and to leaking of BCECF into the extracellular medium occurring during the waiting time and during the measurement procedure. Repeated washing of the suspension reduced in part this contamination but did not eliminate the continuous leakage of BCECF: the specific intracellular signal is progressively reduced. We have examined the use of anion exchange resin (Dowex 1X-8, 200-400 mesh, Cl- form) to bind the extracellular BCECF (negatively charged). Dowex beads glued to one wall of the cuvette out of the optical path constitute an optically neutral sink removing BCECF as it leaks out of the cells. Using this technique, we had estimated the pHi of dog proximal tubule to 7.374 +/- 0.032 at extracellular pH of 7.325 +/- 0.021. The cellular pH is acutely, but transiently, alkalinized by NH4Cl and acidified by Na acetate. The BCECF signal was calibrated using nigericin. This technique improves significantly the measurement of pHi by BCECF fluorescence in tissue suspensions.

Use of anion-exchange resin in F - form in sample processing for determination of carnitine

Use of anion-exchange resin in F - form in sample processing for determination of carnitine

ChemInform Abstract: Use of Anion Exchange Resin in the Synthesis of Aryloxyacetic Acid Esters.

AbstractThe nucleophilic polymer‐supported reagent (I) is obtained by reaction of Amberlite IRA‐400 (chloride form) with the sodium salt of aryloxyacetic acid.

ChemInform Abstract: Polymer Supported Reagents: Use of Anion Exchange Resin in the Synthesis of Aryloxy Acetic Acids.

Abstract Phenoxides supported on Amberlite IRA 400 on reaction with sodium salt of chloroacetic acid gave corresponding aryloxy acetic acid in high yields. Interestingly nitrophenols, 4-hydroxy coumarin and p-hydroxy ethylbenzoate gave excellent yields of the product.

Polymer Supported Reagents: Use of Anion Exchange Resin in the Synthesis of Aryloxy Acetic Acids

Polymer Supported Reagents: Use of Anion Exchange Resin in the Synthesis of Aryloxy Acetic Acids

The Use of an Ion Exchange Resin for Bone Demineralization

Our investigation into the use of ion exchange resin-formic acid combination as an alternative method to other acidextraction procedures is reported. The bone specimens tested were selected from rat and mouse sternums, nasal cavities and ankles. After demineralization, they were routinely stained with hematoxylin and eosin and examined by light microscopy. The results with the resin-formic acid combination showed better tinctorial patterns, good preservation of cellular structures, and excellent definition of nuclear details.

The Use of an Ion Exchange Resin for Bone Demineralization

Our investigation into the use of ion exchange resin-formic acid combination as an alternative method to other acidextraction procedures is reported. The bone specimens tested were selected from rat and mouse sternums, nasal cavities and ankles. After demineralization, they were routinely stained with hematoxylin and eosin and examined by light microscopy. The results with the resin-formic acid combination showed better tinctorial patterns, good preservation of cellular structures, and excellent definition of nuclear details.

L -Serine Production by a Mutant of Sarcina albida Defective in l -Serine Degradation

For improved l-serine production, an l-serine dehydratase-defective mutant of Sarcina albida IAM 1012 was obtained. In the mutant, the activities of the enzymes responsible for l-serine production were as high as those in the parent strain, and, at a low glycine concentration, the mutant accumulated l-serine more efficiently than the parent. Under optimum conditions, 21 mg of l-serine per ml accumulated from 100 mg of glycine per ml. l-Serine was isolated from a reaction mixture as l-serine m-xylene-4-sulfonate, and free amino acid was obtained in high yields by use of an ion-exchange resin. Residual glycine was recovered at a yield of 61%.

An easy student synthesis of a substituted 1,3-dioxane by use of an ion-exchange resin as catalyst: Clean illustration of the Prins reaction

The preparation of 4-(4-hydroxy, 3-methoxy-phenyl) 5-methyl 1,3-dioxane from isoeugenol via the Prins reaction.

Sulfazecin,a novel .BETA.-lactam antibiotic of bacterial origin. Isolation and chemical characterization.

Sulfazecin, a new water-soluble acidic antibiotic, which is active against Gram-negative bacteria, was isolated as crystals from the culture broth of Pseudomonas acidophila G-6302 by use of anion exchange resin and activated charcoal. The molecular formula of sulfazecin was determined to be C12H20N4O9S from physicochemical data. The IR and NMR spectra suggested that this antibiotic has a beta-lactam ring, methoxyl and sulfonate groups. On acidic hydrolysis it gave D-alanine and D-glutamic acid. These chemical and physicochemical data indicated that sulfazecin is a new beta-lactam antibiotic.

Polymer Supported Reagents. The Use of Anion Exchange Resins in the Synthesis of Sulfones

Polymer Supported Reagents. The Use of Anion Exchange Resins in the Synthesis of Sulfones

On the use of anion exchange resin and acidic-organic mixtures in the separation of Na, Cs and Ba

A systematic study was carried out on the adsorption behaviour of Na, Cs and Ba on Dowex 1X8 from various concentrations of hydrochloric and nitric acid solutions. The addition of water-miscible organic solvents to the acidic solutions was found to increase the Kd values for these elements to different extents, which provides a useful method for the separation of carrier-free Ba from irradiated Cs. The effect of kind and content of the different alcohols on the adsorption of Ba was also investigated. It was found that Kd increases with the increase of the alcohol content as well as with the increase of both the dielectric constant and chain length of the alcohol. This effect was found to be more pronounced in the case of nitric acid media.

An improved procedure for the assay of glycogen synthase and phosphorylase in rat liver homogenates

An improved rapid procedure for the separation of labeled glycogen formed in the assay of glycogen synthase (EC 2.4.1.11) in liver homogenates is described. The glycogen formed from UDPG-glucose is separated from phosphate compounds and other electrolytes by passage through a small column of an anion-exchange resin in the acetate or chloride form. The effluent contains glycogen and other polysaccharides and sugars. When the synthase activity is low about half of the labeled glycogen formed in the assay is broken down by amylases or glucosidases, causing an underestimation of the activity by conventional methods of glycogen precipitation. The use of anion-exchange resin avoids this error. From 30 to 70% of the a form of glycogen synthase in rat liver homogenates is in a particulate form found in the pellet centrifuged at 10,000 to 20,000 g. the apparent K m ̂ for UDPG, for both the a and b forms in rat liver homogenates is 0.9 m m. A rapid procedure to assay the two forms of glycogen phosphorylase by separating radioactive glycogen from glucose 1-phosphate with ion-exchange resins is described.

Polymer-Supported Reagents. The Use of Anion-Exchange Resins in the Synthesis of Primary and Secondary Alkyl Fluorides from Alkyl Halides or Alkyl Methanesulfonates

Polymer-Supported Reagents. The Use of Anion-Exchange Resins in the Synthesis of Primary and Secondary Alkyl Fluorides from Alkyl Halides or Alkyl Methanesulfonates

Examination of Some Factors Affecting Sensitivity and Reproducibility in Radioimmunoassay of Thyrotropin

Conditions for measuring human thyrotropin by radioimmunoassay have been investigated, to improve the sensitivity and reproducibility of the assay. The Chloramine-T method of iodination was used, the reaction time being 20 s. Doubling the iodination reaction volume from 55 to 95 mul did not affect the immunoreactivity. Purification of labeled hormone by use of anion-exchange resin followed by silica (Quso G-32) instead of Sephadex gel-filtration or anion exchange alone yielded a product that was the least (less than 4%) contaminated with Na125 I. Human serum albumin (2.5 g/liter) in phosphate-buffered saline, instead of bovine serum, should be used as diluent for unknowns; within-assay variance was 3% for the former, 62% for the latter. The assay worked equally well for both pregnant and nonpregnant patients, with use of 50 to 100 mul of serum per determination. A five-week-old labeled hormone yielded higher values than did two-week-old material. Use of sequential saturation techniques (tracer added on day 3) resulted in a greater than 50% drop in B/B-0 ratio in the standard curve between 0.39 and 50 microunits/ml. Somatotropin, choriomammotropin, and procine insulin did not cross react in this system. Human follitropin and lutropin did cross react, and this cross reaction could not be prevented with as much as 40 international units of human choriogonadotropin per tube. With a total reaction volume of 0.4 ml before addition of second antibody, 0.2 ml of 10-fold diluted second antibody yielded a standard curve with lower nonspecific binding and higher maximum precipitation than one constructed by using only 20 mul of second antibody. In 29 euthyroid patients the mean thyrotropin value was 5.7 microunits/ml (range 2.8-11); nine hypothyroid patients had a mean of 112 microunits/ml (range 38-267); and 13 hyperthyroid subjects showed suppressed thyrotropin with a mean of 3.1 microunits/ml (range 2.2-4.5). Following these suggestions, one can expect a more highly purified immunoreactive tracer and a more sensitive assay than is obtained with the procedure from the Pituitary Agency of the National Institutes of Health.

11] Ion-exchange chromatography of aminoglycoside antibiotics

This chapter discusses the ion-exchange chromatography of aminoglycoside antibiotics. Aminoglycoside antibiotics produced by Streptomyces, Micromonospora, and Bacillus have been extracted and purified by application of an ion-exchange chromatography. More than one aminoglycoside antibiotic is generally produced by the same strain as in cases of kanamycins A, B, and C by Streptomyces kanamyceticus, 1 gentamicins C 1 , C 2 , and C 1a by Micromonospora purpurea and butirosins A and B by Bacillus circulans. Therefore, complete separation of the analogous antibiotics that are produced in a same culture filtrate has been studied. These antibiotics are adsorbed by cation exchangers such as resin, cellulose, and Sephadex ion-exchangers, and separated. Commercially available cation exchangers used for their separation are shown. It is suggested that the most efficient chromatography for separation of analogous aminoglycoside antibiotics can be accomplished by the use of anion exchange resin, Dowex l-X2. This technique by nonionic adsorption chromatography was first employed for separation of kanamycins. Many of the other antibiotics can be purified by this technique.

The Use of Anion-Exchange Resins in the Synthesis of Esters from Carboxylic Acids and Alkylating Agents

The Use of Anion-Exchange Resins in the Synthesis of Esters from Carboxylic Acids and Alkylating Agents

Selective properties and analytical use of an ion-exchange resin based on a-phenylvinylphosphonic acid

The selective properties of a resin based on a copolymer of a-phenylvinyl-phosphonic acid with acrylic acid were investigated. The selectivity of the resin decreases in the order Th(IV) > Sc(III) > Fe(III) > U(VI) > divalent elements. Several interesting separations using the selectivity of this resin are discussed.

Spectrophotometric study of bromide interference in a cholesterol reaction

A spectrophotometric study of the interference of bromide in the ferric chloride reaction for cholesterol has been described. The interference has been shown to be primarily an enhancement of the color reaction and secondarily an additive color owing to a change in the spectrum of the reagent blank. Tested methods of eliminating the interference included removal of bromide by ion exchange, metathetical exchange using AgIO 3, addition of bromide to a reaction plateau and a change in the solvent character of the reaction medium. It was determined that the use of an ion-exchange resin and the substitution of ethanol for acetic acid along with a modified iron reagent were the simplest choices for eliminating bromide interference in this determination. Iodate was shown to depress color formation and it appears to be a detrimental solution to the problem. Further work on the mechanism of the iodate interference is presently in progress.

The Use of Anion Exchange Resin for Determining Available Soil Molybdenum

AbstractAn anion exchange resin (Dowex I‐X4) was used to extract soil Mo from 30 western Oregon hill soils of varying development and derived from different parent materials. The values of Mo extracted by the anion resin increased with soil pH and were reproducible using the thiocyanate colorimetric procedure. Soil Mo so obtained was found to be correlated with plant Mo, plant N, and soil pH.