Developing a universal and simple structure with an excellent fluorescence enhancement is a highly desirable goal for practical applications in optical detection and imaging. Herein, a hybrid structure composed of melamine-formaldehyde (MF) microspheres covering an Au nanorod (AuNR) film (MS/AuNR for short) is reported to enhance fluorescence, which is based on the cooperative effects of a photonic nanojet and plasmon resonance. Moreover, to obtain an excellent plasmonic property, an additional poly(methyl methacrylate) (PMMA) spacing layer with an optimal thickness of 8 nm is added to prevent the fluorescence from directly coming in contact with the AuNR film. Using the proposed hybrid structure and taking the quantum dots (QDs) as fluorescent materials, a maximum enhancement of fluorescence of up to 260 fold is measured. Besides, the hybrid structure is also applied in fluorescence imaging. Utilizing the fluorescence enhancement and pattern magnification effects of the hybrid structure, clear imaging of the 100 nm fluorescent particles is achieved. The above results have important academic value and application prospects in many fields such as weak fluorescence detection and nano-fluorescence imaging.

中文翻译：

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基于光子纳米射流和等离子体共振的协同效应的荧光增强。

对于光学检测和成像中的实际应用而言，开发具有优异荧光增强作用的通用且简单的结构是一个非常理想的目标。在此，基于光子纳米射流和等离子体激元共振的协同作用，报道了由覆盖金纳米棒（AuNR）膜（简称MS / AuNR）的三聚氰胺-甲醛（MF）微球组成的混合结构增强荧光。此外，为了获得优异的等离子体性能，添加了具有8 nm最佳厚度的附加聚甲基丙烯酸甲酯（PMMA）间隔层，以防止荧光直接与AuNR膜接触。使用提出的混合结构并以量子点（QD）作为荧光材料，可以测量到最大260倍的荧光增强。除了，杂化结构也用于荧光成像。利用杂化结构的荧光增强和图案放大效果，可以实现100 nm荧光颗粒的清晰成像。上述结果在弱荧光检测和纳米荧光成像等许多领域具有重要的学术价值和应用前景。