Dil

DiI (CAS 41085-99-8), also referred to as DiIC??(3), is a lipophilic fluorescent probe used primarily for plasma membrane labeling in biological research. Initially exhibiting low fluorescence in solution, DiI significantly increases fluorescence intensity upon incorporation into lipid bilayers, yielding clear orange-red membrane staining. The dye traverses membranes by lateral diffusion, allowing both anterograde and retrograde labeling, making it suitable for neuronal tracing studies. DiI labeling typically preserves cell viability, thus facilitating applications including cell migration assays, cell fusion and adhesion analysis, developmental tracking, and lipoprotein labeling. Additionally, DiI staining is compatible with immunofluorescence techniques using paraformaldehyde fixation.

DiI, also called DiIC₁₈(3), is an orange fluorescent probe that is widely used as a lipophilic tracker in living and fixed tissues and cells. DiI can insert into the membrane, and diffuse rapidly, staining the entire membrane surface orange. DiI usually does not affect cell viability and development, so it is commonly used in cell tracking, such as anterograde and retrograde neuronal tracking. DiI has remained viable for up to four weeks in culture and up to one year in vivo.

DiI staining can be used in conjunction with immunofluorescence. It is recommended to use formaldehyde (PFA) for fixation after DiI staining. Meanwhile, if permeabilization is required, it is suggested to use Triton X-100 or digitonin. But permeabilization may affect the localization of DiI in the cell membrane. In addition, DiI has many other applications including detecting cell-cell fusion and adhesion, tracking cell migration, and labeling lipoproteins.