scholarly journals The interaction between ribonuclease A and surfactants

1973 ◽  
Vol 135 (1) ◽  
pp. 231-236 ◽  
Author(s):  
Malcolm N. Jones ◽  
Henry A. Skinner ◽  
Edward Tipping ◽  
Alan Wilkinson
Keyword(s):  
Cationic Surfactant ◽  
Anionic Surfactant ◽  
Equilibrium Dialysis ◽  
Ribonuclease A ◽  
Enzymic Activity ◽  
Enthalpy Change ◽  
Dodecyltrimethylammonium Bromide ◽  
Difference Spectra

1. U.v. difference spectra show that the anionic surfactant sodium n-dodecyl sulphate unfolds ribonuclease A at pH7.3 and 10.3, but that the cationic surfactant n-dodecyltrimethylammonium bromide does not affect the conformation of the enzyme. 2. Equilibrium-dialysis experiments show that sodium n-dodecyl sulphate binds to ribonuclease A, but no binding of n-dodecyltrimethylammonium bromide could be detected at pH7.3. 3. The enzymic activity of ribonuclease A is unaffected by n-dodecyltrimethylammonium bromide up to a concentration of 0.03m at 25°C. 4. Ultracentrifuge studies support the conclusion that n-dodecyltrimethylammonium bromide does not interact significantly with ribonuclease A. 5. The enthalpy change as measured by microcalorimetry on binding of sodium n-dodecyl sulphate to ribonuclease A is consistent with an exothermic enthalpy of binding occurring simultaneously with an endothermic enthalpy of chain unfolding.

scholarly journals The effect of surfactant structure on ribonuclease A–surfactant interactions

1973 ◽  
Vol 135 (3) ◽  
pp. 547-549 ◽  
Author(s):  
Cecilia Blinkhorn ◽  
Malcolm N. Jones
Keyword(s):  
Anionic Surfactant ◽  
Cationic Surfactants ◽  
Ribonuclease A ◽  
Enzymic Activity ◽  
Head Groups ◽  
Surfactant Interactions ◽  
Dodecylamine Hydrochloride

The enzymic activity of ribonuclease A was measured in the presence of several surfactants at pH7.2. Cationic surfactants with trimethylammonium and pyridinium head groups do not deactivate or denature the enzyme, whereas n-dodecylamine hydrochloride, like the anionic surfactant sodium n-dodecyl sulphate, deactivates and denatures ribonuclease A.

The Effect of Surfactant on the Morphology of SnO2 Nanoarrays

2011 ◽  
Vol 338 ◽  
pp. 495-498
Author(s):  
Ya Li Wang ◽  
Yu Jing ◽  
Qiang Zhen
Keyword(s):  
Nonionic Surfactant ◽  
Hydrothermal Method ◽  
Cationic Surfactant ◽  
Tin Oxide ◽  
Anionic Surfactant ◽  
Indium Tin Oxide ◽  
Polyvinyl Pyrrolidone ◽  
Disordered Structure

The morphology of SnO2nanoarrays prepared on indium tin oxide (ITO) substrates by hydrothermal method can be controlled through using different surfactants. The surfactants play an important role in influencing the morphology and size of SnO2nanoarrays. The rod-like nano-arrays prepared by using cationic surfactant, disordered structure randomly assembled by nanoparticle obtained by using anionic surfactant, the flower-like nanoarrays synthesized by using nonionic surfactant. Furthermore, the effect of the amount of nonionic surfactant-polyvinyl pyrrolidone(PVP) on the morphology and size of flower-like SnO2nanoarrays has systematically been investigated.

Surfactant Effects on Picloram Adsorption by Soils

Weed Science ◽  
1976 ◽  
Vol 24 (6) ◽  
pp. 549-552 ◽  
Author(s):  
J. D. Gaynor ◽  
V. V. Volk
Keyword(s):  
Organic Matter ◽  
Cationic Surfactant ◽  
Anionic Surfactant ◽  
Organic Matter Content ◽  
Clay Content ◽  
Surfactant Solution ◽  
Matter Content ◽  
Adsorption Sites ◽  
Surfactant Solutions ◽  
Extractable Al

The effects of soil organic matter, clay, extractable Al, cation exchange capacity, and pH on the adsorption of picloram (4-amino-3,5,6-trichloropicolinic acid) from aqueous and surfactant solutions were investigated. Linear adsorption isotherms for the soils were obtained with the Freundlich equation. Of the five soil properties investigated, Freundlich K values correlated with extractable Al and clay content. Picloram adsorption from aqueous solutions and from the non-ionic and anionic surfactant solutions was greater on the soils at pH 5 than at pH 7. The anionic surfactant competed with picloram for adsorption sites on the soils at pH 5. Picloram adsorption from solutions containing 0.1 and 1% cationic surfactant was greater than that from aqeuous and anionic and nonionic surfactant solutions. Picloram adsorption from the 10% cationic surfactant solution was similar on soils with pH 5 and 7 and increased with decreased organic matter content.

scholarly journals Anionic surfactant induced desorption of a cationic surfactant from mica

2018 ◽  
Vol 160 ◽  
pp. 276-281 ◽  
Author(s):  
Finian J. Allen ◽  
Chris L. Truscott ◽  
Rebecca J.L. Welbourn ◽  
Stuart M. Clarke
Keyword(s):  
Cationic Surfactant ◽  
Anionic Surfactant
Sign in / Sign up

Export Citation Format

Share Document