Super resolution microscopy (SRM) allows optical microscopy with higher resolutions, beyond the light diffraction limit. The NORBRAIN SRM units offers expertise, services, education, and training to enhance biomedical research through super-resolution-based microscopy.
Equipment and software
Zeiss ELYRA PS.1 SIM/STORM/PALM super-resolution microscope
The main advantage of the Zeiss ELYRA PS.1 system is that users can utilize most existing thin-section samples in a fairly turnkey environment with relatively little supervision.
Three distinct imaging modes are available, depending on the sample type:
- Structured Illumination Microscopy (SIM) is based on patterns of light being projected in the image plane and subsequent post-processing of these images to form a super resolution image. Most thin flourescent samples with standard dyes work without further processing of samples, resolution ‰250 nm. Several dyes can be used simultaneously, axial (Z) resolution is also improved (for 3D localizations), so that a wide-field image is acquired.
- Stochastic Optical Reconstruction Microscopy (STORM) is based on photoswitchable fluorophores to achieve a limited population for sampling. Special chromophores and buffers allow localizations down to ‰20 nm.
- Photo Activated Localization Microscopy (PALM) is based on the precise localization of single, sparsely spaced, fluorescent molecules. In order to achieve sparse spacing only a subset of fluorophores are activated at a time, through photoactivation. This requires special fluorophores and longer scan times to build up images. Z-resolution is improved by TIRF, but carries the same limitaions as TIRF. A resolving power of ≈20 nm (≈10X the diffraction limit) is achievable. Genetically encoded protein tags in tissue sections or cells can be localized within ‰20 nm under ideal conditions.
Software: ZEN2011 Sp2
Example images:
- SIM of Neisseria meningitidis (meningococcus)
- SIM of Mycobacterium marinum
- Widefield and SIM of anti-pilin coloured Neisseria meningitidis (red: anti-pili, blue: DAPI)
Photo: Gunnar F. Lothe, Institutt for medisinske basalfag, UiO.
