Controlled synthesis of dual-emission hierarchical quantum dots hybrid nanostructure as robust ratiometric fluorescent sensor
Controlled synthesis of dual-emission hierarchical quantum dots hybrid nanostructure as robust ratiometric fluorescent sensor
复制标题
双发射分级量子点混合纳米结构的受控合成作为稳健的比率荧光传感器
作者：
Jing Wang;Chenxing Jiang;Fang Yang;Aimin Chen;Ligeng Wang;Jun Hu
构建具有可调强度比和颜色的稳健的双/多发射荧光纳米颗粒在高灵敏度比率探针开发中特别令人感兴趣。在此，我们制备了一种新型的二氧化硅包覆的双发射分级混合纳米结构（CdTe@SiO2@CdTe@SiO2），其中两种尺寸的CdTe量子点（QD）在空间上是分离的，它是由在二氧化硅纳米颗粒表面原位生长的发绿光的QD嵌入发红光的QD组成的。荧光强度比和颜色都可以通过简单地控制外量子点的曝光时间或前体浓度来有效地调节。这种复合物CdTe@SiO2@CdTe@SiO2纳米粒子表现出更强的光和化学稳定性以及更好的生物相容性比以前报道的量子点-二氧化硅-量子点类似物。作为原理的证明，双发射荧光二氧化硅纳米杂化物被用作可靠的比率探针，以通过荧光能量转移机制精确地监测金纳米颗粒浓度。
Constructing robust dual/multi-emission fluorescence nanoparticles with tunable intensity ratios and colors is of particular interest in highly sensitive ratiometric probe development. Herein, we have fabricated a novel silica-coated dual-emission hierarchical hybrid nanostructure (CdTe@SiO2@CdTe@SiO2), with two sizes of CdTe quantum dots (QDs) that were spatially separated, which was composed of green-emitting QDs grown in situ on the surface of silica nanoparticles embedded with red-emitting QDs. Both fluorescence intensity ratios and colors can be effectively adjusted by simple control of refluxing time or precursor concentrations of the outer QDs. This complex CdTe@SiO2@CdTe@SiO2 nanoparticle exhibited stronger photo- and chemical-stability as well as better biocompatibility than previously reported QDs–silica–QDs analogues. As a proof of principle, the dual-emission fluorescent silica nanohybrid was used as a reliable ratiometric probe to precisely monitor gold nanoparticle concentration through a fluorescence energy transfer mechanism.