SYTO 9 stain is an excellent green-fluorescent nuclear and chromosome counterstain that is permeant to both prokaryotic and eukaryotic cell membranes. SYTO 9 stain has a high affinity for DNA and exhibits enhanced fluorescence upon binding with an excitation maximum at 483 nm and fluorescence emission maximum at 503 nm.
SYTO 9 stain is particularly useful as a nuclear counterstain for bacterial assays since it stains both live and dead Gram-positive and Gram-negative bacteria.
