Core/shell nanoparticles composed of a silica core over which a propargyl methacrylate (PMA) shell was polymerized around were synthesized. To employ the shell coating, the surface of the silica nanoparticles (SiNPs) was modified with an alkene-terminated organometallic silane linker that allowed for the covalent attachment of a poly(propargyl methacrylate) (pPMA) shell. The alkyne groups resulting from the pPMA shell were utilized in copper(I)-catalyzed azide/alkyne cycloaddition (CuAAC) reactions to attach azide-modified Förster resonance energy transfer (FRET) pairs of naphthalimide (azNap), rhodamine B (azRhod), and silicon phthalocyanine (azSiPc) derivatives to the shell surface. The luminescence of the system was manipulated by the covalent attachment of one, two, or three of the fluorophores resulting in no energy transfer, one energy transfer, or two energy transfers, respectively. When all three fluorophores were attached to the core/shell particles, an excitation of azNap with a wavelength of 400 nm resulted in the sequential energy transfer between two FRET pairs and the sole emission of azSiPc at 670 nm. These particles may have applications as bioimaging probes as their luminescence is easily detected using fluorescence microscopy.

中文翻译：

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用于多波长生物成像的连续粒子内 Förster 共振能量转移

合成了由二氧化硅核组成的核/壳纳米粒子，在该二氧化硅核上聚合了甲基丙烯酸炔丙酯 (PMA) 壳。为了使用壳涂层，二氧化硅纳米粒子 (SiNPs) 的表面用烯烃封端的有机金属硅烷接头进行了改性，该接头允许聚（甲基丙烯酸炔丙酯）（pPMA）壳的共价连接。由 pPMA 壳产生的炔基团用于铜（I）催化的叠氮化物/炔烃环加成（CuAAC）反应，以连接叠氮化物改性的 Förster 共振能量转移（FRET）对萘酰亚胺（azNap）、罗丹明 B（azRhod）、和硅酞菁 (azSiPc) 衍生物到壳表面。该系统的发光由一个、两个或三个荧光团的共价连接控制，导致没有能量转移，分别进行一次能量转移或两次能量转移。当所有三个荧光团都连接到核/壳颗粒上时，波长为 400 nm 的 azNap 激发导致两个 FRET 对之间的顺序能量转移和 azSiPc 在 670 nm 处的唯一发射。这些粒子可以用作生物成像探针，因为它们的发光很容易使用荧光显微镜检测到。