Encapsulation and Diffusion of Water-Soluble Dendrimers in a Bicontinuous Cubic Phase
2002 (English)In: Langmuir, Vol. 18, no 4, 1073-6 p.Article in journal (Refereed) Published
Bicontinuous cubic (QII) phases composed of hydrated lipids are a unique mesoporous organic material. The diameter of the water channels in the range of 5-10 nm could be used as a reservoir for macromolecular therapeutic agents. Here, we describe the synthesis of water-soluble poly(amidoamine) (PAMAM) dendrimer derivatives labeled with fluorine and their diffusion in the water channels of a QII phase. A QII phase with Ia3d symmetry was prepared by hydration of a 9:1 molar mixture of polymerizable monoacylglycerol and the corresponding 1,2-diacylglycerol. The dendrimers having fluorine were synthesized by Michael reaction of PAMAM dendrimers with a mixture of ethyl 4,4,4-trifluorocrotonate and methyl acrylate. The hydrated diameter of the fluorinated dendrimer of generation 2.5 (G2.5AFH) is 32.6 Å as measured by 19F NMR. The diffusion coefficient of G2.5AFH at 25 C in the water channels of the QII phase, determined by pulsed field gradient 19F NMR spectroscopy, is 1 × 10-12 m2/s, which is compared to the free diffusion coefficient of the dendrimer in water (1.42 × 10-10 m2/s). These data indicate that small globular proteins or similar molecules can diffuse rapidly enough in stabilized QII phases to be technically useful.
Place, publisher, year, edition, pages
2002. Vol. 18, no 4, 1073-6 p.
IdentifiersURN: urn:nbn:se:umu:diva-8726DOI: doi:10.1021/la011173kOAI: oai:DiVA.org:umu-8726DiVA: diva2:148397