I read two references regarding this question. Reference 1 says that FM4-64 majorly stains inner membrane. But reference 2 says FM4-64 stains outer membrane. Anyone knows how does FM4-64 exactly work? Thanks
http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2958.1999.01425.x/full
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0035205