Optical microscopes and optical tweezers, which were invented to image and manipulate microscale objects, have revolutionized cellular and molecular biology. However, the optical resolution is hampered by the diffraction limit; thus, optical microscopes and optical tweezers cannot be directly used to image and manipulate nano-objects. The emerging plasmonic/photonic nanoscopes and nanotweezers can achieve nanometer resolution, but the high-index material structures will easily cause mechanical and photothermal damage to biospecimens. Here, we demonstrate subdiffraction-limit imaging and manipulation of nano-objects by a noninvasive device that was constructed by trapping a cell on a fiber tip. The trapped cell, acting as a biomagnifier, could magnify nanostructures with a resolution of 100 nm (λ/5.5) under white-light microscopy. The focus of the biomagnifier formed a nano-optical trap that allowed precise manipulation of an individual nanoparticle with a radius of 50 nm. This biomagnifier provides a high-precision tool for optical imaging, sensing, and assembly of bionanomaterials.

光学显微镜和光镊的发明是为了对微型物体进行成像和操作，彻底改变了细胞和分子生物学。然而，光学分辨率受到衍射极限的阻碍；因此，光学显微镜和光镊不能直接用于对纳米物体进行成像和操纵。新兴的等离子体/光子纳米镜和纳米镊子可以实现纳米分辨率，但高折射率材料结构很容易对生物样本造成机械和光热损伤。在这里，我们展示了通过将细胞捕获在光纤尖端上而构建的非侵入性设备对纳米物体的亚衍射极限成像和操纵。捕获的细胞充当生物放大器，可以在白光显微镜下放大纳米结构，分辨率为100 nm（λ /5.5）。生物放大器的焦点形成了一个纳米光学陷阱，可以精确操纵半径为 50 nm 的单个纳米颗粒。该生物放大器为生物纳米材料的光学成像、传感和组装提供了高精度工具。