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Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
Evaluation of a cationic calix[4]arene: Solubilization and self-aggregation ability
Elena V Ukhatskaya1, Sergey V Kurkov, Susan E Matthews
1Faculty of Pharmaceutical Sciences, University of Iceland, Hofsvallagata 53, IS-107 Reykjavik, Iceland.
International Journal of Pharmaceutics
|September 23, 2010
Summary
Positively charged aminocalix demonstrates drug solubilizing properties comparable to cyclodextrins, primarily through aggregate interactions, not inclusion complexation. This macrocyclic compound also exhibits unique self-aggregation behavior in aqueous solutions.
Area of Science:
- Supramolecular Chemistry
- Physical Chemistry
- Pharmaceutical Sciences
Background:
- Water-soluble calixarenes are versatile macrocyclic compounds with broad applications.
- Their behavior in aqueous solutions and drug solubilization mechanisms remain underexplored.
- Aminocalix, a positively charged calixarene, presents potential for pharmaceutical applications.
Purpose of the Study:
- To evaluate the drug solubilizing properties of aminocalix.
- To estimate the self-aggregation ability of aminocalix in aqueous solutions.
- To compare aminocalix's performance with pharmaceutically relevant cyclodextrins.
Main Methods:
- Phase-solubility measurements were conducted for various drugs with aminocalix and cyclodextrins.
- Correlation analysis was used to elucidate the drug solubilization mechanism.
- UV-absorbance, osmolality, surface tension, dynamic light scattering, and transmission electron microscopy were employed to study self-aggregation.
Main Results:
- Aminocalix exhibited drug solubilizing ability comparable to cyclodextrins, with maximal enhancement for steroid drugs.
- Correlation analysis suggested that aminocalix solubilizes drugs via interactions with its aggregates, not inclusion complexation.
- Self-aggregation studies indicated the presence of vesicles at 0.1% (w/v) and a reordering transition around 1% (w/v).
Conclusions:
- Aminocalix is an effective drug solubilizer, comparable to cyclodextrins, with a mechanism favoring aggregate interaction.
- The compound displays complex self-aggregation behavior in aqueous solutions, forming vesicles.
- Further research into aminocalix's aggregation and solubilization mechanisms could lead to novel drug delivery systems.
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