| Semiconductor quantum dots (QDs) as high luminescence nanocrystals has attracted considerable attention in recent years, owing to their unique optical and electronic properties. Incorporation of QDs in silica has received considerable attention in the past few years. As silica with a highly cross-linked rigid matrix is ideally suitable for the formation of delicate recognition sites, CdSe@SiO2 were chosen for the study. In this paper, we have researched the preparation and properties of the CdSe@SiO2, and got some innovative results. The specific contents are as follows:Firstly, we report the formation of molecular recognition sites on the surface of silica nanospheres embedded QDs by using molecularly imprinted method (CdSe@SiO2@MIP). When the template was removed by solvent extraction, the MEP-based silica nanospheres are capable of selectively rebinding the target molecule lambdacyhalothrin (LC). Under optimal conditions, the silica nanospheres embedded CdSe QDs with MIP optosensing protocol were demonstrated for simple, rapid, and selective detection of trace LC in water.Secondly, the applications of the core-shell Au-CdSe@SiO2 nanoparticles were studied as'turn on'fluorescence sensors to determinate pyrethroids molecules, the sensitivity is higher than traditional fluorescent sensor.Thirdly, a sensitive identification method of pyrethroids was developed using Ag@SiO2 as colorimetric sensor, and using it for simple and rapidly detection of pyrethroids by color change.Fourthly, design a CdSe@SiO2-based chemosensor transduced through click chemistry, which couple both the optical reporter QDs and cationic receptor (triazoles). As coordinate competition between sulfite anionic and cadmium ions, the fluorescence sensor exhibits several clearly different and reversible fluorescence states that can be controlled by varying sulfite anionic and metal ion concentration. Moreover, the chemosensor was also demonstrated in this contribution to image Cd2+in living HeLa cell. |