Multimodal imaging of cryofixed cells using Raman and fluorescence structured illumination microscopy

Using complementary optical microscopy techniques provides more detailed insight into biological samples. However, misinterpretation can occur by temporal discrepancies due to differences in temporal resolution and switching imaging modalities. Here, we demonstrated multimodal imaging of cryofixed cells using Raman and fluorescence structured illumination microscopy (SIM). Cryofixation preserves structures and chemical states of samples in their near-native states, allowing multimodal imaging without artifacts caused by temporal discrepancy. We demonstrated multimodal imaging of cryofixed HeLa cells stained with an actin probe, where Raman microscope visualized cytochromes, proteins and lipids, and SIM visualized fluorescence-labelled actin filaments.