Beyond the diffraction limit: far-field fluorescence imaging with ultrahigh resolution

Abstract

Fluorescence microscopy is an important and extensively utilised tool for imaging biological systems. However, the image resolution that can be obtained has a limit as defined through the laws of diffraction. Demand for improved resolution has stimulated research into developing methods to image beyond the diffraction limit based on far-field fluorescence microscopy techniques. Rapid progress is being made in this area of science with methods emerging that enable fluorescence imaging in the far-field to possess a resolution well beyond the diffraction limit. This review outlines developments in far-field fluorescence methods which enable ultrahigh resolution imaging and application of these techniques to biology. Future possible trends and directions in far-field fluorescence imaging with ultrahigh resolution are also outlined.

Nanoscale infrared absorption imaging permits non-destructive intracellular photosensitizer localization for subcellular uptake analysis

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Quantifying nanoscale biochemical heterogeneity in human epithelial cancer cells using combined AFM and PTIR absorption nanoimaging

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“…When probing small features such as viruses within a host organism [21], the power of the method for discriminating heterogeneous chemical signals far below the optical diffraction limit becomes apparent. ) present in the spectral derivative (1)(2)(3)(4).…”

Nanoscale optical imaging by atomic force infrared microscopy

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