Structured Illumination Microscopy – What Is It and How Does It Work?

These interference patterns can be produced using a mechanical device with slits, laser projection, or other optical elements. The advantage of optically produced patterns over mechanical is that you can have more flexibility in the type of pattern that’s used – slit vs grid or pinhole – with the latter capable of providing better resolution on complex samples.

This makes SIM ideal for imaging intricate biological structures, such as cytoskeletal filaments, organelles, and protein complexes, which are often smaller than the diffraction limit. Additionally, utilizing structured illumination within fluorescence microscopy can be critical to capture a clear image when working with thicker cells or tissues (organoids are a great example).

The BZ-X800 All-in-one Fluorescence Microscope from KEYENCE employs an optional electronic projection element to optically create slits or grid patterns. This allows users to capture high-resolution images without fluorescence blurring, even on thicker tissues. Contact us to learn more about this technology and how it can improve your research.

The sample is illuminated with a known structured light pattern, often stripes or grids, which interact with the sample’s features to generate moiré fringes.

Multiple images are captured, each with a different phase or orientation of the structured pattern.

Advanced algorithms decode the high-frequency spatial information embedded in the moiré fringes, reconstructing a super-resolved image. This step improves both lateral and axial resolution.

SIM can also be adapted for multicolor imaging and three-dimensional (3D) reconstruction, enabling visualization of complex biological processes in real-time.

SIM is widely used to investigate cellular architecture, such as the organization of organelles like the endoplasmic reticulum, mitochondria, and Golgi apparatus.

The technique has been pivotal in studying synaptic connections and neuronal dynamics, offering insights into brain function and diseases.

Researchers employ SIM to observe embryonic development and morphogenesis, uncovering the spatiotemporal coordination of cellular processes.

SIM has advanced our understanding of how pathogens interact with host cells, aiding in the development of treatments for infectious diseases.

High-resolution imaging of protein complexes and cytoskeletal components helps elucidate molecular mechanisms in health and disease.

With its low phototoxicity, SIM is ideal for studying dynamic biological events such as intracellular transport, cell motility, and membrane dynamics.