These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: AFM and electron microscopy study of the unusual aggregation behavior of metallosurfactants based on iron(II) complexes with bipyridine ligands.
    Author: Garcia P, Eaton P, Geurts HP, Sousa M, Gameiro P, Feiters MC, Nolte RJ, Pereira E, de Castro B.
    Journal: Langmuir; 2007 Jul 17; 23(15):7951-7. PubMed ID: 17569550.
    Abstract:
    The aggregation behavior in water-rich solutions of five iron(II) complexes with alkylated derivatives of 2,2'-bipyridine was studied by electron microscopy (cryo-SEM, SEM, and TEM) and AFM. The results obtained by cryo-SEM on frozen colloidal solutions show that the morphology of the aggregates strongly depends on the length of the alkyl chains in the bipyridine ligands, with shorter alkyl chains forming rod-like structures, whereas for compounds with longer alkyl chains, only spherical structures were detected. The self-aggregates were further characterized by SEM and TEM. The results show that their overall morphology depends only on the length of the alkyl chain of the bipyridine ligands and that the samples show a broad size distribution. In addition, TEM and SEM were used to study the stability of the self-aggregates in solution, the effect of addition of methanol, and the temperature used in the preparation of the colloidal solutions. AFM studies of the aggregates either dried in ambient conditions or dehydrated by long drying under vacuum showed partially collapsed self-aggregates in the latter case, showing that the aggregates contain water in their core, indicating that the self-aggregation leads to vesicle-type structures.
    [Abstract] [Full Text] [Related] [New Search]