Partager

Influence de la méthoxylation des solutés sur la capacité de formation vitreuse et la stabilité des solutions de vitrification.

Effects of solute methoxylation on glass-forming ability and stability of vitrification solutions.

Auteurs : WOWK B., DARWIN M., HARRIS S. B., et al.

Type d'article : Article

Résumé

The effects of replacing hydroxyl groups with methoxyl (OCH3) groups in the polyols ethylene glycol (EG), propylene glycol (PG), glycerol, and threitol were studied by differential scanning calorimetry (DSC) during cooling of aqueous solutions to -150 °C and subsequent rewarming. For 35% (w/w) PG, 40% EG, and 45% glycerol, a single substitution of a terminal hydroxyl group with a methoxyl group reduced the critical cooling rate necessary to avoid ice on cooling (vitrify) from approximately 500 to 50 °C/min. This reduction was approximately equivalent to increasing the parent polyol concentration by 5% (w/w). The critical warming rate calculated to avoid formation of ice on rewarming (devitrification) was also reduced by methoxyl substitution, typically by a factor of 10,000 for dilute solutions. Double methoxylation tended to result in hydrate formation, making these compounds less interesting. An exception was threitol, for which substituting both terminal hydroxyls by methoxyls reduced the critical rewarming rate of a 50% solution by a factor of 10,000,000 without hydrate formation. These glass-forming and stability properties of methoxylated compounds, combined with their low viscosity, enhanced permeability, and high glass transition temperatures, make them interesting candidate cryoprotective agents for cryopreservation by vitrification or freezing.

Détails

  • Titre original : Effects of solute methoxylation on glass-forming ability and stability of vitrification solutions.
  • Identifiant de la fiche : 2001-0545
  • Langues : Anglais
  • Source : Cryobiology - vol. 39 - n. 3
  • Date d'édition : 11/1999

Liens


Voir d'autres articles du même numéro (4)
Voir la source

Indexation