This paper describes ways to multilayer opaline films (opaline heterostructures) composed from functional opal layers of spheres with different lattice constants. At first various monodisperse colloidsboth cross-linked and un-cross-linkedwere prepared from methyl methacrylate, methyl α-chloroacrylate, and methyl α-bromoacrylate. These colloids can be crystallized into large, well-oriented opaline films with the help of a “drawing apparatus” by the method of crystallization in a moving meniscus. After annealing, a second opaline film can be crystallized on top of these films and so on. Electron microscopy inspection shows a sharp borderline between the sublayers and no disorder on both sides although the lattice constants in both films can be incommensurable. Transmission and reflection measurements prove the high quality of the films. The use of a combination of thermolabile and thermostable colloids opens the possibility to prepare functional opaline heterostructures.

Amine-functionalized, chiral mesoporous organosilicas were prepared from a rationally designed precursor, which combines the functions of a network builder, a chiral latent functional group, and a porogen in one molecule. The precursors are formed by a convenient enantioselective hydroboration using (S)-monoisopinocampheylborane on an ethylene-bridged silica precursor. These precursors do selforganize when hydrolysis of their inorganic moiety takes place via an aggregation of their organic moiety into hydrophobic domains. After a condensation-ammonolysis sequence mesoporous organosilicas functionalized with chiral amine groups are obtained, with the complete chiral functionalities located at the pore wall surface and therefore accessible to chemical processes. The pore size of the resulting organosilicas can be fine-tuned using different organic moieties attached to the boron group in the first step. While a wormlike arrangement of pores is observed for the pure precursor, common surfactants can be admixed to further control and tailor the resulting mesoporous system. In certain phase ranges, also chiral periodic mesoporous organosilicas can be obtained.

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The preparation of protein doped silica particles is impeded by the difficulty of incorporating proteins within the silica mesostructure under conditions that do not lead to denaturation. Herein, the synthesis of spherical silica particles (diameter 150 nm-550 nm) under protein friendly conditions in a one step process is described. Diglyceroxysilane (DGS) was reacted in ethanol and methanol-free conditions in pure water or in buffer solutions with or without the presence of additional glycerol. Stabilization of the particles, consistent with steric stabilization, was obtained using poly(ethylene glycol) (PEG) of various molecular weights and with various end groups, including allyl and (CH 2 ) 3 Si(OEt) 3 groups, as a co-reagent. The particles can be prepared at ambient temperature and are reasonably monodisperse in size. At large molecular weights, all PEG led to stable, spherical particles. At lower molecular weights, hydrophobic end groups were necessary to prepare particles. The influence of different molecular weights of PEG, additives and reaction conditions on the size and porosity of particles are analyzed with SEM, TGA and nitrogen adsorption measurements. To demonstrate the biocompatibility of the processing conditions, horse radish peroxidase (HRP) was incorporated into the particles and was observed to remain active for more than 3 months.