Researchers at Osaka University have developed a new super-resolution microscopy technique that allows for sharper images of internal cell structures or cell clusters by using fluorescent molecules that can switch on and off, along with selective illumination in a plane. This technique overcomes the diffraction limit, which limits a microscope’s ability to focus on objects smaller than the wavelength of light being used. By selectively illuminating a desired plane with thin “light sheet” illumination, researchers were able to switch on fluorophores and image dense microstructures inside cells with excellent sharpness. This method allows for background-free super-resolution imaging and is gentler on cells compared to previous methods that involved intense or long exposure to light.
Structured illumination microscopy is one of the super-resolution techniques that can help overcome the diffraction limit by illuminating sinusoidal-patterned light on a sample to obtain sharper images. However, background light from out-of-focus regions can still smear out the final picture. In the study published in the journal Nature Methods, researchers from Osaka University demonstrated a new approach for super-resolution microscopy that allows for observing structures inside a single cell or a cell cluster. By using selective-plane activation, where sinusoidal “structured” light selectively excited a thin plane where on-state fluorophores were localized, researchers were able to achieve background-free super-resolution imaging.
The new super-resolution microscopy technique developed by researchers at Osaka University is particularly effective for studying living systems with spatial structures or 3D cell clusters, including organoids. Organoids are artificial assemblies of different cell types that mimic the behavior of actual body organs better than collections of cells cultured on a flat petri dish. This technique can be useful for future biological studies involving 3D cell clusters, as it allows for high-resolution imaging of internal cell structures without background interference. The researchers believe that their approach can contribute to a better understanding of complex biological systems by providing sharper microscope images that can visualize structures inside cells with excellent sharpness.
Previous methods for super-resolution microscopy have utilized random fluorescence emission from single molecules or “donut” shaped second light sources to deactivate or deplete fluorescent sources outside of a desired area. However, these methods can be damaging to cells due to intense or long exposure to light. The new super-resolution microscopy technique developed by the researchers at Osaka University is gentler on cells and allows for high-resolution imaging of dense microstructures inside cells without causing damage. This method is especially useful for studying living systems with spatial structures or 3D cell clusters, as it provides background-free super-resolution images that can help researchers better understand complex biological processes and systems.
In conclusion, the new super-resolution microscopy technique developed by researchers at Osaka University offers a novel approach for observing internal cell structures or cell clusters with excellent sharpness. By using fluorescent molecules that can switch on and off, along with selective illumination in a desired plane, researchers can achieve background-free super-resolution imaging that is gentler on cells compared to previous methods. This technique is particularly effective for studying living systems with spatial structures or 3D cell clusters, such as organoids, and can provide valuable insights into complex biological processes and systems. The researchers anticipate that their technique will be useful for future biological studies involving 3D cell clusters and other complex biological systems, ultimately advancing our understanding of living organisms at ever smaller length scales.
