Colloidal properties of amiodarone in water at low concentration.
Amiodarone aqueous systems at concentrations C<or=3mg/mL were studied with different techniques (conductivity, solubility, ion-selective electrodes, pH, viscosity, polarizing microscopy, computational simulation, electron microscopy and fluorescence at various temperatures. The Krafft point (T(K)=70.6 degrees C) was determined. A partial phase diagram was plotted showing the critical micelle concentration (CMC) dependence on temperature, the solubility and a transition between a coacervate and an unstable gel below T(K) as a function of temperature. The nature of aggregates below T(K) at different concentrations was determined. Micellization is an entropy-driven process which is probably caused by a strong dehydration of the amiodarone backbone on micellization. CMC, micelle aggregation number and T(K) given in earlier literature were misinterpreted in the original articles and are re-interpreted in this work.
Benedini
Luciano
L
Departamento de Química e INQUISUR, CONICET, Universidad Nacional del Sur, Bahía Blanca, Argentina.
Messina
Paula V
PV
Manzo
Ruben H
RH
Allemandi
Daniel A
DA
Palma
Santiago D
SD
Schulz
Erica P
EP
Frechero
Marisa A
MA
Schulz
Pablo C
PC
D000638:Amiodarone / Q000737:chemistry*; D000889:Anti-Arrhythmia Agents / Q000737:chemistry*; D003102:Colloids / Q000737:chemistry; D005782:Gels / Q000737:chemistry; D008823:Micelles; D008958:Models, Molecular; D012995:Solubility; D013696:Temperature; D014867:Water / Q000737:chemistry
D000889:Anti-Arrhythmia Agents; D003102:Colloids; D005782:Gels; D008823:Micelles; D014867:Water; D000638:Amiodarone