The effect of molecular size on the nasal absorption of water-soluble compounds in the albino rat

1987 ◽  
Vol 39 (5) ◽  
pp. 357-362 ◽  
Author(s):  
A. N. Fisher ◽  
K. Brown ◽  
S. S. Davis ◽  
G. D. Parr ◽  
D. A. Smith
Keyword(s):  
Molecular Size ◽  
Water Soluble ◽  
Nasal Absorption ◽  
Albino Rat

The nasal absorption of sodium cromoglycate in the albino rat

1985 ◽  
Vol 37 (1) ◽  
pp. 38-41 ◽  
Author(s):  
A. N. Fisher ◽  
K. Brown ◽  
S. S. Davis ◽  
G. D. PARR ◽  
D. A. SMITH
Keyword(s):  
Sodium Cromoglycate ◽  
Nasal Absorption ◽  
Albino Rat

COMPARISON OF BARLEY GUMS ISOLATED BY VARIOUS PROCEDURES

1953 ◽  
Vol 31 (7) ◽  
pp. 653-664 ◽  
Author(s):  
W. O. S. Meredith ◽  
T. A. Watts ◽  
J. A. Anderson
Keyword(s):  
Aqueous Solutions ◽  
Molecular Complex ◽  
Alkali Treatment ◽  
Molecular Size ◽  
Degree Of Polymerization ◽  
Aqueous Extraction ◽  
Water Soluble ◽  
Free Sugars ◽  
Enzyme Systems ◽  
Insoluble Form

A barley gum that is believed to be the undegraded, water-soluble, nonstarch polysaccharide of the grain has been isolated. Aqueous solutions of this gum are extremely viscous and are stable. Enzymes that degrade gum during simple aqueous extraction were inactivated first by refluxing barley grist in boiling 85% alcohol followed by extraction of the dried grist with a 1% solution of papain. Gums of lower degree of polymerization, as judged by viscosity measurements, were obtained by aqueous extraction and acid treatments. Two enzyme systems that degrade gums are thought to be present in barley. One (which is inactivated by alcohol) degrades the initially soluble gum and brings an initially insoluble form into solution. The second system (which is inactivated by papain) accompanies and degrades the initially soluble gum during aqueous extraction or in aqueous solutions of the preparation. The purest gum contains only 0.1% nitrogen, and this may be part of the molecular complex. Mild, cold, alkali treatment of this gum reduces molecular size considerably as measured by viscosity of solutions. "X"-enzyme isolated from a bacterial source cleaves the gum into two oligosaccharides of glucose and a component containing D-glucose, L-arabinose, D-xylose, and D-galactose. No free sugars are produced.

scholarly journals Radiochemical Studies of Hydrogen Exchange in Organic Compounds

2021 ◽  
Author(s):  
◽  
Colin Truscott Johnson
Keyword(s):  
Organic Compound ◽  
Grignard Reagent ◽  
Hydrogen Exchange ◽  
Molecular Size ◽  
Water Soluble ◽  
Side Reactions ◽  
Hydrogen Atoms ◽  
Incomplete Reaction ◽  
The One ◽  
Extreme Care

<p>A property of a new or unknown organic compound which must be determined once the empirical formula and molecular weight are known, is the number of active or replaceable hydrogen atoms which the compound contains. These include hydrogen atoms present in amine, hydroxyl, carboxyl and other groups, where the hydrogen is not bound to a carbon atom but to an oxygen, nitrogen or sulphur atom or is in a position where it can ionize. The most general method by which this may be done quantitatively, is the one originally due to Zerewitinoff Zerewitinoff - Berichte 40 2023 (1907) 41 2233 (1908) 42 4802 (1909) 43 3590 (1910) 47 1659 (1914) 47 2417 (1914) and since developed on a micro scale by Roth A. Soltys Mikrochemie 20 107 (1936), Flaschentrager A. Roth Mikrochemie 11 140 (1932), whose method incorporates work by Tschugaeff - Flaschentrager z. Physiol Chem. 146 219 (1923) and the other two authors, and Soltys L. Tschugaeff Berichte 35 3912 (1902), and incorporates many of the latest improvements. This involves the quantatatively evolution of methane from reaction of the Grignard reagent MeMgI on groups such as -SH, -OH, -NH2, -COOH etc., i.e. those groups containing active or replaceable hydrogen atoms. Analysis by this method requires extreme care in technique and exact attention to experimental details. High results are obtained if the solvent or any part of the apparatus contains moisture and the whole determination must be carried out in an atmosphere of nitrogen to avoid reaction of the Grignard reagent with any oxygen present. Low results are obtained if the test solution does not dissolve completely in the chosen solvent and it is essential to carry out a blank prior to each analysis. The proceedure is labourious and painstaking and gives an accuracy of not greater than 5% using 3-5 mgm of organic compound. It also has the disadvantage that the Grignard Reagent will also react with other groups, such as carbonyl, aldehyde, nitrile etc., which may be present. This method cannot be applied to highly water soluble compounds which do not dissolve in ethers or other organic solvents and as the molecular size or complexity of the sample increases, the accuracy of the gasometric reactions becomes less, due to side reactions and incomplete reaction.</p>

scholarly journals Characterization of P(Hema-Gma)-Ida Membrane to Adsorbing Leather Dye

2018 ◽  
Vol 4 (1) ◽  
pp. 10
Author(s):  
Ahmet Aslan ◽  
Safiye Meric Acikel ◽  
Raziye Hilal Senay ◽  
Sinan Akgol
Keyword(s):  
Adsorption Capacity ◽  
Binding Capacity ◽  
Molecular Size ◽  
Cost Effective ◽  
Pollution Source ◽  
Water Soluble ◽  
Leather Industry ◽  
Hydrogel Membranes ◽  
Hydrogel Membrane ◽  
Adsorption Desorption

Different chemical substances and too much water are used during leather production. Therefore, the waste water load of the leather industry is harmful to the environment. One of the pollution source is the production of leather coloring process is a further need to focus on the removal of dye waste waters subject. These water-soluble dyes have a small organic molecular size. Besides the environmental hazards that these dyes cannot be underestimated, they also have harmful effects on human health. In this study, poly (hydroxyethyl methacrylate-glycidyl methacrylate) p (HEMA-GMA) hydrogel membranes were synthesized by UV polymerization method. The hydrogel synthesized is modified with imino diacetic acid (IDA) and then chelated with trivalent chromium ions. The chelating capacity of the membranes were determined according to the time, pH and concentration parameters. Dynamic swelling test, elemental analysis, ninhydrin analysis and adsorption, desorption and reusability performances of membranes were also determined. As a result of the analyzes, it was understood that the hydrogel membrane had high adsorption capacity. The adsorption capacity of the p (HEMA-GMA) -IDA-Cr (III) hydrogel membrane did not decrease even after 5 desorption. At the end of the fifth cycle, the membrane was found to have a dye-binding capacity of about 92%. According to these results, the reusable property of the membrane also makes it cost effective as well as effective adsorption.

FRUCTANS IN ONION BULBS IN RELATION TO STORAGE LIFE

1989 ◽  
Vol 69 (4) ◽  
pp. 1327-1333 ◽  
Author(s):  
MICHIO SUZUKI ◽  
J. A. CUTCLIFFE
Keyword(s):  
Allium Cepa ◽  
Molecular Size ◽  
Degree Of Polymerization ◽  
Storage Life ◽  
Water Soluble ◽  
Soluble Carbohydrates ◽  
High Concentration ◽  
Onion Bulbs ◽  
Storage Carbohydrate ◽  
Water Soluble Carbohydrates

A 3-yr study with eight different onion cultivars, Allium cepa, was conducted to determine the association of water-soluble carbohydrates (WSC) with the storability of the bulbs. Onion bulbs were harvested in the fall of 1983, 1984 and 1985, and sample bulbs were analyzed for WSC. Water-soluble carbohydrates of onion bulbs consisted of a series of oligofructans, the maximum degree of polymerization (DP) being between 10 and 15, in addition to fructose, glucose and sucrose. Fructan concentration of onion bulbs harvested in 1985 decreased during storage. Onion cultivars with a short storage life, such as Buffalo, contained a relatively high moisture content, a high concentration of monosaccharides and a low concentration of fructans at harvest. These criteria may be used as an indicator for identifying onion cultivars with a very short storage life but not for the prediction of storability of onions with medium to long storage life.Key words: Onion, Allium cepa, storage, carbohydrate, fructan, HPLC, molecular size

scholarly journals Cat Heart Muscle in Vitro

1962 ◽  
Vol 46 (2) ◽  
pp. 201-213 ◽  
Author(s):  
Ernest Page
Keyword(s):  
Molecular Size ◽  
Water Soluble ◽  
Osmotic Gradient ◽  
Papillary Muscles ◽  
Total Water ◽  
Inulin Space ◽  
Soluble Molecule ◽  
Cat Heart ◽  
Molecular Radius

The "osmotic gradient" method, an intracellular microelectrode technique for determining whether an uncharged, water-soluble molecule enters cells or remains extracellular, is described. Using this method, a series of carbohydrates of graded molecular size were examined. In cat papillary muscles mannitol, molecular radius 4.0 Å, remained extracellular while arabinose, molecular radius 3.5 Å entered the cells. Measurement of the simultaneous uptake of H3-mannitol and C14-inulin showed that mannitol equilibrates with 40 per cent of total water in 1 hour, after which the mannitol space does not further increase. By contrast, inulin, molecular radius ∼15 Å, equilibrates with 24 per cent of total water in 1 hour; thereafter the inulin space continues to increase very slowly. The intracellular K concentrations are significantly higher and the intracellular Na and Cl concentrations significantly lower when mannitol rather than inulin is used to measure the extracellular space. The intracellular Cl concentration determined with Cl36 or Br82 is significantly higher than that calculated from the membrane potential assuming a passive Cl distribution. In addition, it is shown that choline enters and is probably metabolized by the cells of papillary muscle.

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