Light shines through: A one‐step self‐assembly synthesis of mesoporous silica particles with encapsulated organic dyes (see image) is described. The dyes are physically encapsulated inside nanosize channels/tubes in micrometer‐size silica matrix particles. There is virtually no leakage of the dyes and the fluorescence of the assembled particles is very stable. Much brighter fluorescence can be obtained from the encapsulated dyes than from the same dye in aqueous solution.

We describe a method to study diffusion of rhodamine 6G dye in single silica nanochannels using arrays of silica nanochannels. Dynamics of the molecules inside single nanochannel is found from the change of the dye concentration in solution with time. A 10(8) decrease in the dye diffusion coefficient relative to water was observed. In comparison to single fluorescent molecule studies, the presented method does not require fluorescence of the diffusing molecules.

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To date, the methods of detection of cancer cells have been mostly based on traditional techniques used in biology, such as visual identification of malignant changes, cell growth analysis, specific ligand-receptor labeling, or genetic tests. Despite being well developed, these methods are either insufficiently accurate or require a lengthy complicated analysis. A search for alternative methods for the detection of cancer cells may be a fruitful approach. Here we proposed a novel method for detection of cancer cells in vitro, which is based on non-specific adhesion of silica beads to cells. First, we use atomic force microscopy (AFM) to study adhesion of single silica beads to malignant and normal cells cultured from human cervix. We found that adhesion depends on the time of contact, and can be statistically different for malignant and normal cells. Using these data, we develop an optical method utilizing fluorescent silica beads. The method is based on the detection of difference in the number of adherent particles. The method has been tested using primary cells cultured from cervical tissues of three healthy individuals and three patients with cervical cancer. The method shows sufficiently high sensitivity for cancer to make it interesting to perform further statistical tests.

Growth of even simple crystals is a rather hard problem to describe because of the non-equilibrium nature of the process. Meso(nano)porous silica particles, which are self-assembled in a sol-gel template synthesis, demonstrate an example of shapes of high complexity, similar to those observed in the biological world. Despite such complexity, here we present the evidence that at least a part of the formation of these shapes is an equilibrium process. We demonstrate it for an example of mesoporous fibers, one of the abundant shapes. We present a quantitative proof that the fiber free energy is described by the Boltzmann distribution, which is predicted by the equilibrium thermodynamics. This finding may open up new ground for a quantitative description of the morphogenesis of complex self-assembled shapes, including biological hierarchy.