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A series of mesoporous nanosphere materials that are functionalized with various terminal and bridging organic groups were synthesized. They have improved adsorption capacity and different release properties for drug and small molecules. The materials contained terminal vinyl, 3-mercaptopropyl, 3-aminopropyl, and secondary amine functional groups and bridging ethane, ethene, and benzene groups within their mesopore channel walls. The samples containing mercaptopropyl and vinyl groups showed greater adsorption capacity and better controlled release behavior for rhodamine 6G molecules. On the other hand, mesoporous matrices containing amine functional groups showed higher adsorption capacity and better release properties for ibuprofen molecules. Further studies revealed that the bridging organic groups in the mesopore channel walls also improved the adsorption capacity and release properties of the materials compared to the corresponding samples containing no bridging organic groups. Such improved adsorption and controlled release properties of molecules by simple changes of functional groups on mesoporous materials are important for the development of nanomaterial drug delivery vehicles and for controlled release of drugs over long time periods at specific targeted sites in the body. By judicious choice of organic groups and by systematic design and synthetic approaches, nanoporous materials having different adsorption capacity and release properties for many other drug molecules can also be achieved.

SPnoPeisGrignard reagentrinitiated polymerization of thietane gave a soluble crystalline polymer melting at 59°C. Oxidation of the polymer with one or two equivalents of hydrogen peroxide gave the sulfoxide and sulfone, respectively. The sulfoxide was noncrystalline and insoluble in all common solvents at mom temperature and softened at 185-200°C. The sulfone was partially orystalline and insoluble. * This polymer (MW 2000, m.p. 5657°C. has been reported earlier from the reaction of sodium with bis(ychloropropy1) sulfide by Hurd and Wilkinson.3 171

Fluorescence and absorption spectra of hydrophobic sunscreens, weakly fluorescent octyl methoxycinnamate, moderately fluorescent octyl salicylate and highly fluorescent 2‐ethylhexyl‐4‐(dimethylamino) benzoate (padimate O) adsorbed to dielectric microspheres in aqueous suspension, have been compared with spectra in organic solution. The fluorescence of adsorbed salicylate and padimate is enhanced compared with fluorescence in methanol: about a factor of 6 and 30 in terms of fluorescence yield per molecule of salicylate and padimate, respectively, Cinnamate, which has a low fluorescence yield, does not show a comparable fluorescence enhancement. The fluorescence amplification is independent of sphere diameter from 30 to 1500 nm, at least for salicylate. The enhancement, as well as the location of absorption spectral peaks, is consistent with a low‐dielectric constant environment of the molecules, in spite of the presumed location near the interface between polystyrene (E = 2.4–3.8) and water (E = 78). The adsorbed state of these sunscreens represents a proposed improved in vitro model for the environment of sunscreens in vivo, as well as a general model for chromphores in heterogeneous environments.