Improved thyroxine radioimmunoassay, for filter paper discs saturated with dried blood.

1976 ◽  
Vol 22 (11) ◽  
pp. 1912-1914 ◽  
Author(s):  
M L Mitchell
Keyword(s):  
Anion Exchange ◽  
Filter Paper ◽  
Large Scale ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Clinical Signs ◽  
Excellent Correlation ◽  
Experimental Conditions ◽  
Large Scale Screening

Abstract I describe an improved procedure for estimating thyroxine in dried blood on 0.32-cm filter paper discs, by radioimmunoassay. A weak anion-exchange resin is used to separate free and antibody-bound radiothyroxine and, by measuring the resin-bound 125I-labeled thyroxine rather than the supernatant radioactivity, a tedious and cumbersome step is eliminated. The unique properties of the resin permit considerable latitude in the experimental conditions, in contrast with charcoal, without compromising sensitivity or precision. There is excellent correlation between thyroxine values obtained from discs and those of the corresponding plasmas. Application of this procedure for large-scale screening of newborns has proved to be highly successful in identifying thyroid insufficiency in several babies before clinical signs were apparent.

A simple method of polyamine purification

1985 ◽  
Vol 38 (4) ◽  
pp. 633 ◽  
Author(s):  
IW Stapleton
Keyword(s):  
Aqueous Solution ◽  
Anion Exchange ◽  
Large Scale ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Simple Procedure ◽  
Crystalline Solid ◽  
Simple Method

A simple procedure for the large-scale purification of commercial polyethyleneamines (H2N[CH2CH2NH]nH where n = 2-5) is described in which the per- tosylate salt separates as a crystalline solid from aqueous solution. The salts require no further purification except for pentaethylenehexamine (n = 5), which requires recrystallization from water. The free bases are regenerated from the tosylate salt by an anion-exchange resin.

Highly efficient separation of ruthenium from alkaline radioactive feeds using an anion exchange resin

2020 ◽  
Vol 108 (8) ◽  
pp. 603-613 ◽  
Author(s):  
Parveen Kumar Verma ◽  
Prasanta Kumar Mohapatra
Keyword(s):  
Anion Exchange ◽  
Alkaline Medium ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Solid Phase ◽  
Alkaline Media ◽  
Anionic Complex ◽  
Back Extraction ◽  
Column Studies ◽  
Experimental Conditions

AbstractRuthenium recovery from the alkaline media was attempted using solid phase extraction. UV-Vis and X-ray absorption studies were performed to understand the ruthenium speciation under different conditions relevant to its extraction from alkaline medium. Since Ru forms anionic complex in the alkaline solution, an anion exchange resin (Dowex 1x8) was selected for its recovery from alkaline media. The precipitation of black RuO2 at the resin surface hinders its back exaction. Experimental conditions were optimized for the quantitative uptake of Ru from alkaline feed and its subsequent back extraction by a series of batch studies. About 90 % of the Ruthenium was back extracted from the resin using alkaline hypochlorite solution and nitric acid solution at different stages in the Ru back extraction cycle. The column studies were done under the optimized condition and showed ~80 % Ru recovery with 5 mL of the eluent (8 M HNO3) and ~90 % recovery in 10 mL including the tailing. The mechanism for the ruthenium extraction from alkaline medium and its back extraction from the resin was proposed.

scholarly journals Removal of Chromium(VI) from Aqueous Solution using a Strong base Anion Exchange Resin : Kinetic and Equilibrium Studies

2021 ◽  
Author(s):  
HARISH NAGESH REVANKAR ◽  
PRASANNA S KOUJALAGI ◽  
VIJAYENDRA R GURJAR ◽  
RAVIRAJ M KULKARNI
Keyword(s):  
Aqueous Solution ◽  
Anion Exchange ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Exchange Process ◽  
Maximum Adsorption Capacity ◽  
Experimental Conditions ◽  
Equilibrium Studies ◽  
Strong Base ◽  
Chromium Vi

Abstract The removal of chromium (VI) from aqueous solution using the strong base anion exchange resin Tulsion A-62 (MP) is reported in this study under a variety of experimental conditions, including initial chromium (VI) concentration, contact time, and medium pH. The ion-exchange process for the resin Tulsion A-62 (MP) was relatively simple and after 300 minutes of phase contact, the equilibrium was achieved. The sorption process, which is pH based, extracted the most chromium (VI) when the pH was between 4.0 and 5.0. Both Langmuir and Freundlich adsorption isotherms were used to fit the equilibrium results for Cr(VI) adsorption, however Langmuir isotherm model was found to be more acceptable for the Cr(VI) adsorption and maximum adsorption capacity of Cr(VI) was found to be 201.6 mg/g. Scanning Electron Microscopy with EDX and Fourier transformed infrared spectroscopy were also used to characterize Tulsion A-62 (MP) before and after chromium adsorption. The adsorption mechanism followed reversible first-order kinetics. The findings showed that such anion-exchange resins can be used to effectively extract chromium (VI) ions from water and wastewater.

scholarly journals Concentration of rhenium from dilute sodium chloride solutions

2008 ◽  
Vol 73 (3) ◽  
pp. 333-339 ◽  
Author(s):  
Dragoljub Lukic ◽  
Jurij Vucina ◽  
Slobodan Milonjic
Keyword(s):  
Sodium Chloride ◽  
Anion Exchange ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Elution Profile ◽  
Experimental Conditions ◽  
Sodium Chloride Solutions ◽  
Low Efficiency ◽  
The Given ◽  
Dowex 1

The conditions for the desorption of rhenium from the anion exchange resin Dowex 1-x8 by HNO3, HCl, H2SO4 and NaOH were determined. The solution (5.0?10-3 mol dm-3 Re in 0.15 mol dm-3 NaCl) was passed through a column containing 0.10 g of the resin. The total sorbed amount of rhenium was 0.20 g/g of the resin. It was then eluted by the corresponding eluent in the concentration range up to about 3.0 mol dm-3. The highest elution efficiency and the most favourable elution profile were found with 3.0 mol dm-3 HNO3. Over 77 % of the sorbed rhenium was found in the first 5 ml of the eluate. Practically all the rhenium was recovered with 20 ml of the acid. Under the given experimental conditions, HCl and H2SO4 were less favourable while NaOH was not applicable, due to very low efficiency of rhenium elution.

scholarly journals Large Scale Solid Phase Synthesis of Peptide Drugs: Use of Commercial Anion Exchange Resin as Quenching Agent for Removal of Iodine during Disulphide Bond Formation

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
K. M. Bhaskara Reddy ◽  
Y. Bharathi Kumari ◽  
Dokka Mallikharjunasarma ◽  
Kamana Bulliraju ◽  
Vanjivaka Sreelatha ◽  
...  
Keyword(s):  
Anion Exchange ◽  
Large Scale ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Bond Formation ◽  
Side Reactions ◽  
Preparative Hplc ◽  
Protecting Group ◽  
Peptide Drugs ◽  
Large Scale Synthesis

The S-acetamidomethyl (Acm) or trityl (Trt) protecting groups are widely used in the chemical synthesis of peptides that contain one or more disulfide bonds. Treatment of peptides containing S-Acm protecting group with iodine results in simultaneous removal of the sulfhydryl protecting group and disulfide formation. However, the excess iodine needs to be quenched or adsorbed as quickly as possible after completion of the disulfide bond formation in order to minimize side reactions that are often associated with the iodination step. We report here a simple method for simultaneous quenching and removal of iodine and isolation of disulphide bridge peptides. The use of excess inexpensive anion exchange resin to the oxidized peptide from the aqueous acetic acid/methanol solution affords quantitative removal of iodine and other color impurities. This improves the resin life time of expensive chromatography media that is used in preparative HPLC column during the purification of peptide using preparative HPLC. Further, it is very useful for the conversion of TFA salt to acetate in situ. It was successfully applied commercially, to the large scale synthesis of various peptides including Desmopressin, Oxytocin, and Octreotide. This new approach offers significant advantages such as more simple utility, minimal side reactions, large scale synthesis of peptide drugs, and greater cost effectiveness.

PEMODELAN MATEMATIS ADSORPSI CO2 DENGAN STRONG BASE ANION EXCHANGE RESIN SEBAGAI ADSORBEN UNTUK PURIFIKASI BIOGAS

2015 ◽  
Vol 5 (1) ◽  
pp. 11
Author(s):  
Anies Mutiari ◽  
Wiratni Wiratni ◽  
Aswati Mindaryani
Keyword(s):  
Anion Exchange ◽  
Pilot Plant ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Scale Up ◽  
Sum Of Squares ◽  
Strong Base ◽  
Model Transfer ◽  
Plant Parameter

Pemurnian biogas telah banyak dilakukan untuk menghilangkan kadar CO2  dan meningkatkan kandungan CH4  yang terkandung di dalamnya. Kandungan CH4 yang tinggi akan memberikan unjuk kerja yang lebih baik. Model  matematis proses adsorpsi CO2 disusun berdasarkan teori lapisan film antar fasa, dimana pada proses yang ditinjau terdapat tiga fase yaitu gas, cair dan padat. Model matematis dari data eksperimental   kecepatan dan kesetimbangan proses adsorpsi CO2 melalui mekanisme pertukaran ion di suatu kolom adsorpsi telah dibuat. Model ini dibuat untuk mencari konstanta yang dapat dipergunakan pada proses scale up data laboratorium ke skala pilot plant. Parameter proses kecepatan yang dicari nilainya adalah koefisien transfer massa massa volumetris CO2 pada fase cair (kLa), koefisien transfer massa volumetris CO2 pada fasegas (kGa) dan tetapan laju reaksi (k1 dan k2). Pada hasil penelitian ini ditunjukkan bahwa nilai parameter yang diperoleh sesuai hasil fitting data dengan model matematis yang digunakan, yaitu model transfer massa pada lapisan film antar fase secara seri: adalah kGa, kla, k1 dan k2  dengan nilai Sum of Squares Error (SSE) rata-rata 0,0431. Perbandingan nilai kGa hasil simulasi dan teoritisnya memberikan kesalahan rata-rata 18,79%. Perbandingan nilai kLa hasil simulasi dan teoritis memberikan kesalahan rata-rata 7,92%.Kata kunci: model matematis, adsorpsi CO2, pemurnian biogas

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