Scanning superlens microscopy for non-invasive large field-of-view visible light nanoscale imaging

Abstract

Nanoscale correlation of structural information acquisition with specific-molecule identification provides new insight for studying rare subcellular events. To achieve this correlation, scanning electron microscopy has been combined with super-resolution fluorescent microscopy, despite its destructivity when acquiring biological structure information. Here we propose time-efficient non-invasive microsphere-based scanning superlens microscopy that enables the large-area observation of live-cell morphology or sub-membrane structures with sub-diffraction-limited resolution and is demonstrated by observing biological and non-biological objects. This microscopy operates in both non-invasive and contact modes with ∼200 times the acquisition efficiency of atomic force microscopy, which is achieved by replacing the point of an atomic force microscope tip with an imaging area of microspheres and stitching the areas recorded during scanning, enabling sub-diffraction-limited resolution. Our method marks a possible path to non-invasive cell imaging and simultaneous tracking of specific molecules with nanoscale resolution, facilitating the study of subcellular events over a total cell period.

High Resolution Surface Metrology Using Microsphere‐Assisted Interference Microscopy

“…It can be noted that while using smaller diameter microspheres results in an increase in the lateral resolution, the field of view is decreased . On the other hand, for larger diameter microspheres (>20 μm), the resolving power decreases while the field of view increases . The use of microspheres having a dimeter around 24 μm is a compromise between resolving power and field of view.…”

Unibody microscope objective tipped with a microsphere: design, fabrication, and application in subwavelength imaging

“…In addition, optical trapping method was reported to control the microsphere, however, this method was limited to liquid environment [26]. The most effective way among the previously published research is the manipulation of single microsphere lens by tip-based scanning techniques [27][28][29]. In 2016, F. Wang et al bonded BTG microsphere onto an AFM tip, with the advantage of precise positioning and feedback monitoring, the system has high precision in maintaining distance between microsphere and objects.…”

Illumination conditions in microsphere‐assisted microscopy

“…Furthermore, it presents the advantages of being label free and providing a high resolution in the full field (Darafsheh et al, 2014) in comparison to other farfield imaging techniques such as those based on spatial filtering (Minsk, 1961), the Pendry hyperlens (Pendry, 2000), the scanning photonic jet (Heifetz et al, 2007), the scattering lens (Putten et al, 2011) or the submerged microsphere (Li et al, 2013). In addition, microsphere-based ultramicroscopy only requires the use of a classical optical microscope.By placing a glass transparent microsphere on or above (Wang et al, 2016a) an object, a magnified virtual image appears below the object, as shown in Fig. 1.…”

“…However, the objective lens must be able to resolve the magnified features of the virtual image generated by the microsphere. Although the phenomenon of microsphereassisted microscopy is still not fully explained and the claimed resolution values are debatable (Allen et al, 2015), several experimental results and computer simulations have not only determined the role of evanescent waves (Ben-Aryeh, 2016), the influence of the surrounding medium (Yao et al, 2015;Darafsheh, 2017) and the effect of the coherence (Maslov & Astratov, 2016;Perrin et al, 2017a), but also improved the field of view using stitching techniques (Wang et al, 2016a;Huszka et al, 2017). Moreover, microsphere-assisted microscopy has been successfully combined with interferometry for the three-dimensional (3D) topography reconstruction of nanostructures (Wang et al, 2016b;Perrin et al, 2017b;Kassamakov et al, 2017) or cell morphology (Aakhte et al, 2017), and with dark-field illumination for the imaging of translucent biological samples .…”