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Amino-functionalized mesoporous silica of different pore sizes and pore system dimensionalities is used as a host material for the inclusion of fluorescein (non-covalent host-guest interaction) and fluorescein isothiocyanate (covalent host-guest interaction). The parameters determining the achievable guest loading depend on the type of host-guest interaction. For covalent interaction, the loading is mainly determined by the accessibility of the adsorption sites, while a more complex situation was encountered in case of non-covalent interactions. In addition to the accessibility of the adsorption sites, an interpretation of the results needs to take into account the confinement of the included guests, as well as the distribution of the adsorption sites.

; Dolamic, I; Gartmann, N (2009Abstract: The defined pore networks of silicate-based molecular sieves are attractive for the development of highly organized inorganic/organic hybrid materials. Efficient energy transfer systems are obtained upon inclusion of dye molecules into the one-dimensional channels of zeolite L. The resulting host-guest materials form the basis for an advanced luminescent solar concentrator. The selective functionalization of the channel entrances with zinc phthalocyanine offers further possibilities in terms of employing the dye-zeolite composites for the sensitization of organic solar cells. Having larger pore sizes than zeolites as well as highly modifiable channel walls, mesoporous silicas have recently emerged as versatile starting materials for the synthesis of drug delivery devices. One of the most challenging aspects in this context is the control and the analysis of the functional group distribution. This topic is discussed on the basis of our recent work on the reaction of aminopropylalkoxysilanes with mesoporous silica MCM-41.

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A simple method to create self-organized patterns of microparticles in polymer films is demonstrated. Dye-loaded zeolite crystals are used as model microparticles, allowing convenient imaging of the patterns by fluorescence microscopy. The pattern formation can be interpreted within the general framework of the model of local self-activation and lateral inhibition. Two starting parameters, namely the polymer concentration and the wet film thickness, control the size and shape of the particle aggregates in the patterns, as well as their spacing. The size of the aggregates ranges from 50 to 340 µm. Self-Organized Patterns of Microparticles in Polymer FilmsChristophe Bauer, Nando Gartmann, Le-Quyenh Dieu, Nora Zuber, Igor Dolamic, Jan H.