Polarity Nano-Mapping of Polymer Film Using Spectrally Resolved Super-Resolution Imaging

Abstract

With the rapid development of the nanofabrication of polymer materials, the local measurement of the chemical properties of polymer nanostructures has become crucial because they can be highly heterogeneous at the nanoscale. We developed a spectroscopic imaging approach to characterize the nanoscale local polarity of polymer films via spectrally resolved super-resolution microscopy. We demonstrate the capability of the recently developed single-molecule sensing and imaging method to probe the polarity of polymers either inside a polymer matrix or on the external surface of a polymer. The nanoscale polarity sensing capability of our method facilitates the differentiation of various polymer surfaces based on chemical polarities, and it can further differentiate the polarity of functional side chain groups. Moreover, we demonstrate that a two-component polymer mixture can be locally distinguished based on the contrasting polarities of the lateral phase separation, further allowing for the investigation of nanoscale phase separation depending on the composition of the polymer blend film. This approach is anticipated to open the door to further characterizations of various nanocomposite materials.

Recent development of computational cluster analysis methods for single-molecule localization microscopy images

“…This method has also been shown to quantify the ultrastructural changes of various organelles, such as mitochondria, dense tubular system (DTS), autophagosomes, α-granules, and dense granules, in platelet during the platelet activation and division process [35] , [36] . It was also successfully employed to identify and quantify the phase separation in polymer blend films on the nanoscale [37] . The identified boundaries of each phase were further processed for the analysis of specific interfacial lengths and areas.…”

Spectroscopic single-molecule localization microscopy: applications and prospective

“…Typical sSMLM images of f 5:1, g 1:1, and h 1:5 mixes of PVC/PIB polymer blends. Scale bars: 5 μm (Reprinted with permission from [ 41 ]) …”

“…Several groups applied sSMLM and NR to classify materials’ surface properties. For example, Park et al characterized the nanoscopic properties, in particular, polarity, of polymer materials [ 41 ]. They spin-coated mixed polymer and NR solutions onto glass coverslips and used sSMLM to map the polarity of different polymer materials.…”

Development of Highly Dense Material-Specific Fluorophore Labeling Method on Silicon-Based Semiconductor Materials for Three-Dimensional Multicolor Super-Resolution Fluorescence Imaging

“…This difficulty may be overcome by light microscopy, which enables molecular-specific imaging without the requirement of a vacuum system. Although light microscopy suffers from the inherent diffraction of light, the recent development of the super-resolution fluorescence microscopy (SRM) technique over the past decade has drastically improved the resolution of light microscopy to ∼10 nm. − The new opportunities afforded by SRM have motivated extensive research, providing multidimensional and multiscale information about a system regarding its morphology, functionality, dynamics, and chemical composition. − This novel technique has shown remarkable applications in biological studies, but its application to materials has still been limited owing to the requirement for fluorophore tagging procedure on inorganic materials with a high labeling density.…”