Hofmeister Effect in Coagels from Ascorbic Acid-based Surfactants

LO NOSTRO, PIERANDREA; BARRY NINHAM,; MOIRA AMBROSI,; LAURA FRATONI,; SANTIAGO PALMA,; DANIEL ALBERTO ALLEMANDI; RUBEN MANZO,; PIERO BAGLIONI,

LANGMUIR

ACS

Año: 2003 vol. 19 p. 9583 - 9583

0743-7463

p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: justify; tab-stops: list 14.2pt">Ascorbyl-6-O-alkanoates (ascorbyl-O-CO-(CH2)n-1H, in brief ASCn) are single chain anionic surfactants. When dispersed in water at room temperature, they produce coagels. At higher temperatures, these hydrated crystalline phases form either micellar solutions or gel phases, depending on the length of the aliphatic tail. The different phase behavior reflects the interplay between interactions that involve the ionic headgroups and water, and those between the hydrophobic chains. Solute induced modification of water structure ¨C e.g. by adding sucrose or urea - induce significant changes in the coagel-to-gel or coagel-to-micelle phase transitions.