Binding of lead and copper(II) ions to starch and amylose 2,3-dicarboxy derivatives

1986 ◽  
Vol 51 (5) ◽  
pp. 1160-1169 ◽  
Author(s):  
Rudolf Kohn ◽  
Karol Tihlárik
Keyword(s):  
Ionic Strength ◽  
Multiple Equilibria ◽  
Copper Ions ◽  
Metal Cations ◽  
Lead Ions ◽  
High Concentration ◽  
Counter Ion ◽  
Ion Activity ◽  
Degree Of Association ◽  
Derivatives Of

The binding of Pb2+ and Cu2+ ions to starch and amylose 2,3-dicarboxy derivatives of degrees of oxidation DO = 0.09-0.74 was investigated. The interaction of the metal cations with the carboxy groups of the derivatives was evaluated in terms of the counter-ion activity, determined with ion specific electrodes. The binding is very strong; at DO ≥ 0.34, lead ions are bound quantitatively ( degree of association β = 0.999), copper ions are also bound to a great extent (β = 0.94-0.97). The complexation of copper with the ligands at ionic strength I = 0.15 mol 1-1 was treated in terms of multiple equilibria theory. Different complexes were found in dependence on the concentration ratios of the reactants; at a high excess of COO- groups with respect to Cu2+ ions, the latter are strongly bound and the number of COO- groups binding a Cu2+ cation is greater than 2, whereas at a sufficiently high concentration of Cu2+ ions the number of COO- groups binding a Cu2+ cation approaches the stoichiometric value of 2.

Binding of cadmium and copper(II) ions to oligogalacturonic acids

1983 ◽  
Vol 48 (7) ◽  
pp. 1922-1935 ◽  
Author(s):  
Rudolf Kohn ◽  
Kveta Heinrichová ◽  
Anna Malovíková
Keyword(s):  
Uronic Acid ◽  
Multiple Equilibria ◽  
Carboxyl Groups ◽  
Polymerization Degree ◽  
Indicator Method ◽  
Ion Activity ◽  
Elimination Mechanism ◽  
Single Ion Activity ◽  
Degree Of Association ◽  
Positively Charged

The binding of Cu2+ and Cd2+ ions to potassium oligogalacturonates of polymerization degree DP 1 to 9 was investigated by ion-specific electrodes and by the metallochromic indicator method. The interaction was evaluated on the basis of degree of association β of cations (M2+) with carboxyl groups of the compounds examined and the single-ion activity coefficients of counterions γM2+. The results were compared with values corresponding to an electrostatic bond of Ca2+ ions to these oligomers. The Cd2+, and especially Cu2+ ions were bound in a considerable measure already to mono- and oligogalacturonates of a low polymerization degree very probably by a chelate bond. Precipitation of Cu- and Cd-oligogalacturonates takes place at a polymerization degree DP 5 and 8, respectively. Interpretation of results by the multiple equilibria theory evidenced that the Cu2+ ions were stoichiometrically bound to mono- and oligogalacturonates (one cation to two carboxyl groups) similarly, as with polymeric D-galacturonan. The results revise the early conception concerning the formation of a positively charged complex of Cu2+ ions (similarly also of Cd2+ and Pb2+ ions) with monogalacturonic acid of (MA)+ type, where A- is the anion of uronic acid. The results are a contribution to the elucidation of the elimination mechanism of these toxic cations from human body involving the oligomeric fragments of pectin as products of its enzymic degradation in the digestive tract.

An Evaluation of a Plasma Fractionation System

1960 ◽  
Vol 4 (01) ◽  
pp. 031-044
Author(s):  
George Y. Shinowara ◽  
E. Mary Ruth
Keyword(s):  
Biological Activity ◽  
Ionic Strength ◽  
Plasma Proteins ◽  
High Concentration ◽  
Significant Evidence ◽  
Native Proteins ◽  
Mobility Data ◽  
Fractionation Procedure ◽  
The Individual ◽  
Low Ionic Strength

SummaryFour primary fractions comprising at least 97 per cent of the plasma proteins have been critically appraised for evidence of denaturation arising from a low temperature—low ionic strength fractionation system. The results in addition to those referable to the recovery of mass and biological activity include the following: The high solubilities of these fractions at pH 7.3 and low ionic strengths; the compatibility of the electrophoretic and ultracentrifugal data of the individual fractions with those of the original plasma; and the recovery of hemoglobin, not hematin, in fraction III obtained from specimens contaminated with this pigment. However, the most significant evidence for minimum alterations of native proteins was that the S20, w and the electrophoretic mobility data on the physically recombined fractions were identical to those found on whole plasma.The fractionation procedure examined here quantitatively isolates fibrinogen, prothrombin and antithrombin in primary fractions. Results have been obtained demonstrating its significance in other biological systems. These include the following: The finding of 5 S20, w classes in the 4 primary fractions; the occurrence of more than 90 per cent of the plasma gamma globulins in fraction III; the 98 per cent pure albumin in fraction IV; and, finally, the high concentration of beta lipoproteins in fraction II.

Binding of calcium and lead ions to carboxystarch prepared by action of nitrogen dioxide on native starch and its 2,3-dialdehyde derivatives

1986 ◽  
Vol 51 (6) ◽  
pp. 1340-1351 ◽  
Author(s):  
Rudolf Kohn ◽  
Karol Tihlárik
Keyword(s):  
Nitrogen Dioxide ◽  
Alkaline Medium ◽  
Binding Capacity ◽  
Lead Ions ◽  
Carbonyl Groups ◽  
Weakly Alkaline ◽  
Exchange Cations ◽  
Counter Ions ◽  
The Stability ◽  
Derivatives Of

The binding of calcium and lead ions to carboxy derivatives of starch prepared by allowing nitrogen dioxide to act on native maize starch (procedure A) and on starch 2,3-dialdehyde derivatives of degrees of oxidation DO(d.a.) ≥ 0.94 (procedure B) was studied. The carboxy group content of the samples in the H+ form was 4.6 - 12.1 mmol g-1. The effect of alkaline medium on the stability of the carboxy derivatives and on their ability to bind and exchange cations was examined. The Ca2+ → 2K+ exchange was evaluated in terms of the decrease in the electrostatic free enthalpy Δ(Gel/N)KCa, determined by alkalimetric potentiometric titrations, and the binding of Pb2+ ions was evaluated in terms of the activity of the Pb2+ counter-ions determined in suspensions of Pb salts of the carboxy derivatives by means of an ion specific electrode. The IR and CD spectra revealed that the carboxystarch preparations obtained by procedure A contained, in addition to free carboxy groups, a considerable amount of carbonyl groups. During the conversion of the latter groups to the former, even in a weakly alkaline medium, the carboxy derivatives undergo an appreciable degradation and lose, to a great extent, their ability to bind and exchange cations. Procedure B, on the other hand, leads to highly selective starch and amylose carboxy derivatives, exhibiting a small amount of carbonyl groups and featuring a relative stability towards alkaline medium; their binding capacity is as high as 12 milliequivalents of cations per g of sample.

Effects of ionic strength on inclusion body refolding at high concentration

2017 ◽  
Vol 130 ◽  
pp. 100-106 ◽  
Author(s):  
Jakub Gabrielczyk ◽  
Jonas Kluitmann ◽  
Thorben Dammeyer ◽  
Hans-Joachim Jördening
Keyword(s):  
Ionic Strength ◽  
Inclusion Body ◽  
High Concentration

INBORN ERROR OF HISTIDINE METABOLISM

PEDIATRICS ◽  
1962 ◽  
Vol 29 (5) ◽  
pp. 714-728
Author(s):  
H. Ghadimi ◽  
M. W. Partington ◽  
A. Hunter
Keyword(s):  
Ferric Chloride ◽  
Urocanic Acid ◽  
High Concentration ◽  
Normal Children ◽  
Total Lack ◽  
Normal Urine ◽  
One Year ◽  
The One ◽  
Blue Eyes ◽  
Derivatives Of

A 3-year-old girl with fair hair and blue eyes came under observation because of speech retardation. The patient was given a phenylalanine-free diet, since persistently positive urine tests with ferric chloride and reagent strips (Phenistix) were strongly suggestive of phenylketonuria. On further investigation she was found to be suffering from a totally different and not heretofore recognized condition, the salient features of which were an abnormally high concentration of histidine in the blood and an excessive output of histidine in the urine. The child's sister, one year older, presented the same metabolic anomaly. In each case both the concentration of histidine in plasma and the daily output were directly related to the amount of protein in the diet; but even at their lowest levels they greatly exceeded those of normal children of the same age. An oral load of histidine was followed by an increase of histidine in plasma much higher and more prolonged than that observed in controls, and by the excretion of a much larger fraction of the ingested dose. The urine of each sister contained not only excessive amounts of histidine but also notable quantities of imidazole-pyruvic, imidazole-acetic, and imidazole-lactic acid, histidine derivatives of which normal urine contains only traces. It is concluded that in the two sisters the normally predominant pathway of histidine catabolism, which leads through urocanic acid to glutamic acid, was partially or completely blocked. Since, even after histidine loading, the urines never contained detectable amounts of urocanic acid, the block must precede the formation of that substance. The condition presented is therefore due primarily to a deficiency or total lack of histidine-alpha-deaminase; the enzyme which converts histidine to urocanic acid. As a result of this defect histidine is forced to take the alternative but less efficient pathway which begins with its transamination to imidazole-pyruvic acid. This substance is the one responsible for positive reactions in the ferric chloride and Phenistix tests. All urine specimens examined, whether from the patient or from normal controls, contained considerable quantities of an unidentifiable imidazole compound ("X"), which does not appear to have been previously reported. The existence of this substance may call for some modification of current concepts of histidine metabolism in man.

Speciation and Geochemical Implications of Carcass Burial Leachate

2018 ◽  
Vol 61 (2) ◽  
pp. 559-570
Author(s):  
Dyan L. Pratt ◽  
Terrance A. Fonstad
Keyword(s):  
Chemical Composition ◽  
Ionic Strength ◽  
Activity Coefficient ◽  
Swine Manure ◽  
Burial Site ◽  
Mass Mortality Event ◽  
Ammonium N ◽  
Ion Activity ◽  
Common Activity ◽  
The Impact

Abstract. In the event of a mass livestock mortality situation, disposal routes such as burial are commonly chosen. The impact of burial on the environment could be substantial, but the composition of the leachate arising from a burial site has not been well documented. This study was performed to determine the chemical composition of leachate arising from animal mortalities in a burial setting. Three species of livestock were used: bovine, swine, and poultry. Leachate collected from lined burial pits over two years of decomposition was analyzed for major and minor ions. Analysis indicated that livestock mortality leachate contains, on average, concentrations of 46,000 mg L-1 of alkalinity (as bicarbonate), 12,600 mg L-1 of ammonium-N, 2600 mg L-1 of chloride, 3600 mg L-1 of sulfate, 2300 mg L-1 of potassium, 1800 mg L-1 of sodium, and 1500 mg L-1 of phosphorus, along with lesser amounts of iron, calcium, and magnesium. Select samples had maximum concentrations of ammonium-N and bicarbonate up to 50% higher than these average values. In comparison to earthen swine manure storages and landfills, the ionic strength of the leachate was 2 to 4 times higher, and therefore its impact on water resources could be greater. Following the study of the chemical composition of livestock mortality leachate, the potential impacts of this leachate on the soil/water systems below a burial site were investigated. The ionic strength of the leachate presents its own set of challenges. Basic modeling of ion activity using the five most common activity coefficient equations (Debye-Hückel, extended Debye-Hückel, Truesdell-Jones, Davies, and Pitzer) were considered to assess the sensitivity of these methods for calculated ion activity as impacted by the ionic strength of the leachate. This was completed to further enhance the modeling and speciation efforts. Based on the results and the applicability of the Truesdell-Jones equation, PHREEQC was used to assess the chemical speciation of the leachate. The speciation of this leachate provides evidence of phosphate and sulfate compounds available for potential unattenuated transport. Understanding the geochemical implications of livestock mortality burial will give scientists and regulators more information for performing future risk analyses when considering mortality burial as a management option, either routinely or during a mass mortality event. Keywords: Ion activity coefficient, Ionic strength, Leachate chemical composition, Livestock burial leachate, Speciation.

Methoxy-substituted derivatives of 1,4-bis(2-phenylethenyl)benzene and of 1,4-bis(2-phenylethyl)benzene as ligands in ion-selective electrodes for lead ions

2001 ◽  
Vol 18 (1-2) ◽  
pp. 171-176 ◽  
Author(s):  
Iwona Szymańska ◽  
Katarzyna Ocicka ◽  
Hanna Radecka ◽  
Jerzy Radecki ◽  
H.J. Geise ◽  
...  
Keyword(s):  
Lead Ions ◽  
Ion Selective Electrodes ◽  
Derivatives Of

Bonding

1938 ◽  
Vol 11 (1) ◽  
pp. 169-186
Author(s):  
B. J. Habgood
Keyword(s):  
Natural Rubber ◽  
New Method ◽  
Bonding Agent ◽  
Butadiene Rubber ◽  
High Concentration ◽  
Chloro Derivatives ◽  
Brass Plating ◽  
Derivatives Of

Abstract 1. Neoprene and rubber can be bonded directly, provided that: (a) the composition of the two stocks are balanced; (b) the stocks are kept warm; (c) bonding is carried out with the minimum of delay. 2. Neoprene and rubber can be bonded by other methods which give greater latitude of working: (a) by the use of a high concentration of accelerator at the interface; (b) by the use of a tie-gum mix made from butadiene rubber (preferably sodium-polymerized); (c) by the use of mixtures of Neoprene, chloro derivatives of rubber, either alone or admixed with rubber. Partially hydrochlorinated rubber is particularly useful in this direction. 3. Synthetic rubbers can be bonded one to another or to natural rubber either directly or through the medium of sodium-butadiene rubber. 4. The bonding of rubber to metal has been considered and the main methods discussed, including bonding by means of ebonite; alloys, particularly brass; cyclorubbers, Thermoprenes, and cements. 5. The bonding of synthetic rubbers to metals has been examined and a new method of bonding Neoprene to a variety of metals, including iron, steel, aluminum, zinc, and lead, has been worked out, using a solution of chlorinated rubber as bonding agent. 6. By combining the various methods described in this paper, rubber may be bonded to metals such as aluminum without brass plating.

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