scholarly journals THE KINETICS OF OSMOSIS

1927 ◽  
Vol 10 (6) ◽  
pp. 883-892 ◽  
Author(s):  
John H. Northrop
Keyword(s):  
Osmotic Pressure ◽  
Egg Albumin ◽  
Kinetics Of

It is shown that by combining the osmotic pressure and rate of diffusion laws an equation can be derived for the kinetics of osmosis. The equation has been found to agree with experiments on the rate of osmosis for egg albumin and gelatin solutions with collodion membranes.

scholarly journals THE KINETICS OF EXOSMOSIS OF WATER FROM LIVING CELLS

1927 ◽  
Vol 10 (5) ◽  
pp. 659-664 ◽  
Author(s):  
Morton McCutcheon ◽  
Baldwin Lucke
Keyword(s):  
Osmotic Pressure ◽  
Salt Concentration ◽  
Driving Force ◽  
Temperature Characteristic ◽  
Living Cells ◽  
Velocity Constant ◽  
Osmotic Equilibrium ◽  
Kinetics Of

1. The rate of exosmosis of water was studied in unfertilized Arbacia eggs, in order to bring out possible differences between the kinetics of exosmosis and endosmosis. 2. Exosmosis, like endosmosis, is found to follow the equation See PDF for Equation, in which a is the total volume of water that will leave the cell before osmotic equilibrium is attained, x is the volume that has already left the cell at time t, and k is the velocity constant. 3. The velocity constants of the two processes are equal, provided the salt concentration of the medium is the same. 4. The temperature characteristic of exosmosis, as of endomosis, is high. 5. It is concluded that the kinetics of exosmosis and endosmosis of water in these cells are identical, the only difference in the processes being in the direction of the driving force of osmotic pressure.

The transmembrane gradient of osmotic pressure modifies the kinetics of sodium currents in perfused neurons

1983 ◽  
Vol 39 (5) ◽  
pp. 494-495 ◽  
Author(s):  
O. A. Krishtal ◽  
Yu. V. Osipchuk ◽  
V. I. Pidoplichko
Keyword(s):  
Osmotic Pressure ◽  
Sodium Currents ◽  
Kinetics Of

scholarly journals ION SERIES AND THE PHYSICAL PROPERTIES OF PROTEINS. I

1920 ◽  
Vol 3 (1) ◽  
pp. 85-106 ◽  
Author(s):  
Jacques Loeb
Keyword(s):  
Oxalic Acid ◽  
Physical Properties ◽  
Osmotic Pressure ◽  
Chloride Solution ◽  
Dibasic Acid ◽  
Egg Albumin ◽  
Phosphoric Acids ◽  
Acid Salts

1. This paper contains experiments on the influence of acids and alkalies on the osmotic pressure of solutions of crystalline egg albumin and of gelatin, and on the viscosity of solutions of gelatin. 2. It was found in all cases that there is no difference in the effects of HCl, HBr, HNO3, acetic, mono-, di-, and trichloracetic, succinic, tartaric, citric, and phosphoric acids upon these physical properties when the solutions of the protein with these different acids have the same pH and the same concentration of originally isoelectric protein. 3. It was possible to show that in all the protein-acid salts named the anion in combination with the protein is monovalent. 4. The strong dibasic acid H2SO4 forms protein-acid salts with a divalent anion SO4 and the solutions of protein sulfate have an osmotic pressure and a viscosity of only half or less than that of a protein chloride solution of the same pH and the same concentration of originally isoelectric protein. Oxalic acid behaves essentially like a weak dibasic acid though it seems that a small part of the acid combines with the protein in the form of divalent anions. 5. It was found that the osmotic pressure and viscosity of solutions of Li, Na, K, and NH4 salts of a protein are the same at the same pH and the same concentration of originally isoelectric protein. 6. Ca(OH)2 and Ba(OH)2 form salts with proteins in which the cation is divalent and the osmotic pressure and viscosity of solutions of these two metal proteinates are only one-half or less than half of that of Na proteinate of the same pH and the same concentration of originally isoelectric gelatin. 7. These results exclude the possibility of expressing the effect of different acids and alkalies on the osmotic pressure of solutions of gelatin and egg albumin and on the viscosity of solutions of gelatin in the form of ion series. The different results of former workers were probably chiefly due to the fact that the effects of acids and alkalies on these proteins were compared for the same quantity of acid and alkali instead of for the same pH.

scholarly journals THE KINETICS OF PENETRATION

1938 ◽  
Vol 22 (2) ◽  
pp. 147-163 ◽  
Author(s):  
A. G. Jacques
Keyword(s):  
Osmotic Pressure ◽  
Free Space ◽  
Partition Coefficients ◽  
Sea Water ◽  
Intact Cell ◽  
Linear Part ◽  
Osmotic Concentration ◽  
Intact Cells ◽  
Rate Of Increase ◽  
Kinetics Of

When Valonia cells are impaled on capillaries, it is in some ways equivalent to removing the comparatively inelastic cellulose wall. Under these conditions sap can migrate into a free space and it is found that on the average the rate of increase of volume of the sap is 15 times what it is in intact cells kept under comparable conditions. The rate of increase of volume is a little faster during the first few hours of the experiment, but it soon becomes approximately linear and remains so as long as the experiment is continued. The slightly faster rate at first may mean that the osmotic pressure of the sap is approaching that of the sea water (in the intact cell the sap osmotic pressure is always slightly above that of the sea water). This might result from a more rapid entrance of water than of electrolyte, as would be expected when the restriction of the cellulose wall was removed. During the linear part of the curve the osmotic concentration and the composition of the sap suffer no change, so that entrance of electrolyte must be 15 times as fast in the impaled cells as it is in the intact cells. The explanation which best accords with the facts is that in the intact cell the entrance of electrolyte tends to increase the osmotic pressure. As a consequence the protoplasm is partially dehydrated temporarily and it cannot take up more water until the cellulose wall grows so that it can enclose more volume. The dehydration of the protoplasm may have the effect of making the non-aqueous protoplasm less permeable to electrolytes by reducing the diffusion and partition coefficients on which the rate of entrance depends. In this way the cell is protected against great fluctuations in the osmotic concentration of the sap.

scholarly journals The osmotic pressure of crystalline egg-albumin

1929 ◽  
Vol 23 (5) ◽  
pp. 1079-1089 ◽  
Author(s):  
John Marrack ◽  
Leslie Frank Hewitt
Keyword(s):  
Osmotic Pressure ◽  
Egg Albumin

Kinetics of the acid denaturation of egg albumin

1951 ◽  
Vol 33 (2) ◽  
pp. 345-346 ◽  
Author(s):  
Robert J. Gibbs ◽  
M. Bier ◽  
F.F. Nord
Keyword(s):  
Egg Albumin ◽  
Acid Denaturation ◽  
Kinetics Of

scholarly journals FURTHER STUDIES ON THE KINETICS OF OSMOSIS IN LIVING CELLS

1931 ◽  
Vol 14 (3) ◽  
pp. 405-419 ◽  
Author(s):  
Balduin Lucké ◽  
H. Keffer Hartline ◽  
Morton McCutcheon
Keyword(s):  
Cell Surface ◽  
Osmotic Pressure ◽  
Volume Change ◽  
Living Cells ◽  
Arbacia Punctulata ◽  
Kinetics Of ◽  
And Diffusion ◽  
Swelling And Shrinking

Using unfertilized eggs of Arbacia punctulata as natural osmometers an attempt has been made to account for the course of swelling and shrinking of these cells in anisotonic solutions by means of the laws governing osmosis and diffusion. The method employed has been to compute permeability of the cell to water, as measured by the rate of volume change per unit of cell surface per unit of osmotic pressure outstanding between the cell and its medium. Permeability to water as here defined and as somewhat differently defined by Northrop is approximately constant during swelling and shrinking, at least for the first several minutes of these processes. Permeability is found to be independent of the osmotic pressure of the solution in which cells are swelling. Water is found to leave cells more readily than it enters, that is, permeability is greater during exosmosis than during endosmosis.

scholarly journals Sieving and reflection coefficients for sodium salts and glucose during peritoneal dialysis in rats.

1991 ◽  
Vol 2 (6) ◽  
pp. 1092-1100
Author(s):  
T W Chen ◽  
R Khanna ◽  
H Moore ◽  
Z J Twardowski ◽  
K D Nolph
Keyword(s):  
Peritoneal Dialysis ◽  
Osmotic Pressure ◽  
Peritoneal Cavity ◽  
Pressure Gradients ◽  
Peritoneal Membrane ◽  
Rat Serum ◽  
Cycle Times ◽  
Dialysis Solution ◽  
Kinetics Of ◽  
Sodium Sieving

The two-part studies reported herein address peritoneal membrane ultrafiltrate (UF) characteristics during peritoneal dialysis exchanges in rats. In the studies of part 1, the sieving coefficients for sodium, chloride, and total solutes during hydrostatic UF after instillation of rat serum into the peritoneal cavity of rats were calculated. Thirty-six rats were divided into six groups (N = 6) according to the following peritoneal dialysis exchange cycle times: 60, 120, 180, 240, 480, and 960 min. Thirty milliliters of pooled rat serum were infused i.p. with the animal being conscious except during infusion and drainage. The study showed in the early phase of exchanges, when oncotic and osmotic pressure gradients were absent, net UF presumably due to capillary hydrostatic pressure and sodium sieving during such UF. Sieving coefficients for sodium (0.72), chloride (0.77) and total solutes (0.73) were determined by using standard formulae. In the second part of these studies, the kinetics of fluid movement after the instillation of 5% dextrose solution into the peritoneal cavity of rats were analyzed. A very low UF rate was observed early in the exchange when the glucose gradient between the dialysis solution and blood was at its peak. The UF rate gradually increased as the sodium entered the dialysis solution from the blood. At the time of low UF rate with high glucose gradient, presumably the osmotic pressure generated by the glucose in the dialysis solution was countered by the osmotic pressure of solutes in plasma, i.e., sodium and its anions.(ABSTRACT TRUNCATED AT 250 WORDS)

Heating and Chemical Denaturation of Egg Albumin Matrix and its Effect on the Release Kinetics of Theophylline from Tablets

2004 ◽  
Vol 7 (9) ◽  
pp. 1488-1492 ◽  
Author(s):  
Sharif Md. Shaheen ◽  
Mamunur Rashid . ◽  
Md. Anwar ul Islam . ◽  
Reza Ul Jalil .
Keyword(s):  
Release Kinetics ◽  
Chemical Denaturation ◽  
Egg Albumin ◽  
Kinetics Of
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