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We present a flexible method for multiplexed colour encoded silica nanospheres encapsulating layers of different colour quantum dots by a reverse microemulsion method.These QDs@SiO2 spheres with multi-QDs/SiO2 layers are not only highly uniform and show strong luminescence,but also encapsulated QDs throughout the bead(from the core to the shell).Furthermore,QDs with different colour were separated in the different space of beads,which prevent the potential energy transfer process between QDs and make the precise encoding easier.This procedure is expected to embed or encode a variety of beads with QDs and other nanospecies such as magnetic iron oxide nanoparticles and colloidal metal nanoparticles too.So,the multilayered,core/shell nanoprobes based on magnetic nanoparticles and QDs have been successfully developed for multimodality tumor imaging.The nanosensor can be used both as a fluorescent probe and a contrast reagent of magnetic resonance imaging.In vivo multimodality images of breast tumors were successfully taken by NIR fluorescence and T2-weighted magnetic resonance.The nanoprobes have great potential to use for multimodality imaging of cancer tumors in vitro and in vivo.Furthermore,QD-Au NP@silica mesoporous microspheres have been fabricated as a novel enzyme-mimic nanosensor.As biomimetic catalyst,Au NPs in the mesoporous silica shell can catalytically oxidize glucose as glucose oxidase(GOx)-mimicking.The resultant hydrogen peroxide can quench the photoluminescence signal of QDs in the microsphere core.Therefore the nanosensor based on the decrease of the PL intensity of QDs was established for the glucose detection.The proposed procedure is also expected to embed QDs and a variety of functional nanoparticles to form other novel kinds of nanosensors.