Highly Bright Expansion Microscopy
121st Summer Symposium of KCS-Physical Chemistry Division (2016)
Expansion microscopy (ExM), which uses physically enlarged samples embedded in a swellable polymer matrix, surpass the diffraction limit in spatial resolution with conventional microscopes. When combined with super-resolution fluorescence microscopy, ExM may open new windows to achieve the ultimate resolution of a few nanometers. However, expanded samples in ExM have lower labeling density that makes it hard to be directly applied to super-resolution microscopy. Here we introduce a labeling method that increases the labeling density of ExM by using the tyramide signal amplification and/or the biotin/avidin interaction. We amplified the fluorescence intensity of expanded samples, and quantitatively examined the amplification efficiencies with confocal microscopy. With this approach, ExM can provide additional four- or five-fold increment of spatial resolution in super-resolution microscopy to visualize the ultrastructures with single-digit resolution.
References
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