A new publication from Opto-Electronic Advances ; DOI 10.29026/oea.2024.

240035 discusses multiplexed stimulated emission depletion nanoscopy for multi-color live-cell long-term imaging. In the field of cell biology, an increasing number of studies are focusing on the intricate network of interactions among subcellular structures. As a powerful imaging tool, super-resolution fluorescence microscopy broke the diffraction limit, enabling biologists to observe subcellular structures with nanoscale resolution.

Among super-resolution fluorescence microscopy, stimulated emission depletion microscopy (STED) is one of the leading techniques beyond the diffraction limit, and it ensures minimal artifacts by its immediate super-resolution microscopic properties without post-processing. In the last decade, the need to study the interactions between subcellular structures has led to an increasing interest and application of multicolor live-cell STED, most conventionally achieved by using multiple excitation-depletion beam pairs. However, increasing the number of depletion beams not only makes the system more complex and dramatically increases the construction cost, but also increases the likelihood of photo-bleaching and more severe photo-cytotoxicity, which is not conducive to live-cell imaging.

On the other hand, the use of a single depletion beam along with multiple excitation beams limits the range of available excitation wavelengths, and dividing the restricted band into multiple dens.