Solubilization of Amphiphilic Carboxylic Acids in Nonionic Micelles:  Determination of Partition Coefficients from pKaMeasurements and NMR Experiments

Langmuir ◽  
2007 ◽  
Vol 23 (21) ◽  
pp. 10463-10470 ◽  
Author(s):  
Laurence Dupont-Leclercq ◽  
Sébastien Giroux ◽  
Bernard Henry ◽  
Patrice Rubini
Keyword(s):  
Carboxylic Acids ◽  
Partition Coefficients

The Use of Piezosensors for Determination of Carboxylic Acids in the Intermediate Products of Edible Ethanol Production

2020 ◽  
Vol 56 (14) ◽  
pp. 1379-1383
Author(s):  
Cao Nhat Linh ◽  
O. V. Duvanova ◽  
S. Yu. Nikitina ◽  
A. N. Zyablov
Keyword(s):  
Ethanol Production ◽  
Carboxylic Acids ◽  
Intermediate Products

Interphase distribution of 2-furylethylenes

1985 ◽  
Vol 50 (8) ◽  
pp. 1642-1647 ◽  
Author(s):  
Štefan Baláž ◽  
Anton Kuchár ◽  
Ernest Šturdík ◽  
Michal Rosenberg ◽  
Ladislav Štibrányi ◽  
...  
Keyword(s):  
Partition Coefficient ◽  
Partition Coefficients ◽  
Transport Rate ◽  
Phase System ◽  
Two Phase ◽  
Interphase Distribution ◽  
Distribution Kinetics ◽  
System 1 ◽  
Kinetics Of

The distribution kinetics of 35 2-furylethylene derivatives in two-phase system 1-octanol-water was investigated. The transport rate parameters in direction water-1-octanol (l1) and backwards (l2) are partition coefficient P = l1/l2 dependent according to equations l1 = logP - log(βP + 1) + const., l2 = -log(βP + 1) + const., const. = -5.600, β = 0.261. Importance of this finding for assesment of distribution of compounds under investigation in biosystems and also the suitability of the presented method for determination of partition coefficients are discussed.

scholarly journals Expert System for Catalytic Titrimetry—Part 2: Determination of Monobasic Carboxylic Acids

1998 ◽  
Vol 81 (5) ◽  
pp. 1077-1086
Author(s):  
Biljana F Abramovic ◽  
Borislav K Abramovic ◽  
Ferenc F Gaál ◽  
Danilo M Obradovtc
Keyword(s):  
Expert System ◽  
Carboxylic Acids ◽  
Selective Determination

Abstract An expert system (ES) to solve the problem of choosing a catalytic titrimetric procedure for determining monobasic carboxylic acids is described. Carboxylic acids were divided into 3 groups—aliphatic, aromatic, and α-aminocarboxylic acids— based on their behavior in catalytic titrations with different indicator reactions, titrant, and/or solvent and the possibility of their selective determination in the presence of other acids

scholarly journals Evidence for two asymmetric conformational states in the human erythrocyte sugar-transport system

1975 ◽  
Vol 145 (3) ◽  
pp. 417-429 ◽  
Author(s):  
J E Barnett ◽  
G D Holman ◽  
R A Chalkley ◽  
K A Munday
Keyword(s):  
Glucose Transport ◽  
Transport System ◽  
Human Erythrocyte ◽  
Partition Coefficients ◽  
External Medium ◽  
Sugar Transport ◽  
Conformational States ◽  
Glucose Transport System ◽  
Oil Water

6-O-methyl-, 6-O-propyl-, 6-O-pentyl- and 6-O-benzyl-D-galactose, and 6-O-methyl-, 6-O-propyl- and 6-O-pentyl-D-glucose inhibit the glucose-transport system of the human erythrocyte when added to the external medium. Penetration of 6-O-methyl-D-galactose is inhibited by D-glucose, suggesting that it is transported by the glucose-transport system, but the longer-chain 6-O-alkyl-D-galactoses penetrate by a slower D-glucose-insensitive route at rates proportional to their olive oil/water partition coefficients. 6-O-n-Propyl-D-glucose and 6-O-n-propyl-D-galactose do not significantly inhibit L-sorbose entry or D-glucose exit when present only on the inside of the cells whereas propyl-beta-D-glucopyranoside, which also penetrates the membrane slowly by a glucose-insensitive route, only inhibits L-sorbose entry or D-glucose exit when present inside the cells, and not when on the outside. The 6-O-alkyl-D-galactoses, like the other nontransported C-4 and C-6 derivatives, maltose and 4,6-O-ethylidene-D-glucose, protect against fluorodinitrobenzene inactivation, whereas propyl beta-D-glucopyranoside stimulates the inactivation. Of the transported sugars tested, those modified at C-1, C-2 and C-3 enhance fluorodinitrobenzene inactivation, where those modified at C-4 and C-6 do not, but are inert or protect against inactivation. An asymmetric mechanism is proposed with two conformational states in which the sugar binds to the transport system so that C-4 and C-6 are in contact with the solvent on the outside and C-1 is in contact with the solvent on the inside of the cell. It is suggested that fluorodinitrobenzene reacts with the form of the transport system that binds sugars at the inner side of the membrane. An Appendix describes the theoretical basis of the experimental methods used for the determination of kinetic constants for non-permeating inhibitors.

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