Fig. 5
From: Escherichia coli recombinant sperm immobilizing factor RecX as a potential vaginal contraceptive
Eosin staining of mouse spermatozoa after 20 s of incubation with (a) PBS, unstained head (live) spermatozoa. (b Recombinant sperm immobilizing factor, pink stained head (dead) spermatozoa. Magnification for both a and b: 400X.