Magnetic luminescent nanocomposites were prepared via a layer-by-layer (LbL) assembly approach. The Fe3O4 magnetic nanoparticles of 8.5 nm were used as a template for the deposition of the CdTe quantum dots (QDs)/polyelectrolyte (PE) multilayers. The number of polyelectrolyte multilayers separating the nanoparticle layers and the number of QDs/polyelectrolyte deposition cycles were varied to obtain two kinds of magnetic luminescent nanocomposites, Fe3O4/PE n /CdTe and Fe3O4/(PE3/CdTe) n , respectively. The assembly processes were monitored through microelectrophoresis and UV−vis spectra. The topography and the size of the nanocomposites were studied by transmission electron microscopy. The LbL technique for fabricating magnetic luminescent nanocomposites has some advantages to tune their properties. It was found that the selection of a certain number of the inserted polyelectrolyte interlayers and the CdTe QDs loading on the nanocomposites could optimize the photoluminescence properties of the nanocomposites. Furthermore, the nanocomposites could be easily separated and collected in an external magnetic field. It provides a novel technological innovation for luminescent tagging applications in biomedicine and biotechnology, such as rapid, convenient separation in vitro or site-specific transport in vivo due to the excellent magnetic properties of the nanocomposites.

In this paper, we report a novel route to the synthesis of high-quality, large-pore periodic mesoporous organosilicas (PMOs) using triblock copolymer P123 as a template. The novelty lies in that highly ordered PMOs can only be synthesized at a limited range of low acid concentrations, which differs from traditional approach to the synthesis of similar materials including large-pore periodic mesoporous silicas (PMSs). The role that acid plays in the synthesis of high-quality PMOs and PMSs was critically examined, compared, and interpreted.