Nuclear imaging Propidium Iodine
PI (Propidium Iodine; Ex: 536 nm – Em: 617 nm)
Read SDS in cupboard PI is considered highly carcinogenic: use gloves and a face mask when preparing the concentrated stock solution, and use gloves when handling the working solution.
Principal
When PI is bound to nucleic acids, the fluorescence excitation maximum is 535 nm and the emission maximum is 617 nm. PI binds to DNA by intercalating between the bases with little or no sequence preference and with a stoichiometry of one dye per 4–5 base pairs of DNA. PI is membrane impermeable and generally excluded from viable cells making it suitable to identify dead cells in a population (See Fluorometric cell viability essay).
Preparation of reagents
- dissolve 1 mg/ml in H2O to generate the stock solution (store in fridge)
- To obtain 1X concentration dissolve 10 μl stock solution into 1ml PBS
Microscope filter system
Excitation energy can be supplied with a xenon or mercury-arc lamp or with the 488nm line of an argon-ion laser. PI emits at a maximum wavelength of 617 nm.
