Figure 4.

Vaginal tissue distribution of nanoparticle preparations following intraperitoneal and intravaginal delivery. (A) Mice received fluorescein-Poly(Lactic-Co-Glycolic Acid (PLGA) nanoparticles IVAG and vaginal tissue was excised 2 h later. (B) Mice received fluorescein-PLGA nanoparticles via IP injection and vaginal tissue was excised 24 h later. (C) H₂O was administered IP as a negative control and vaginal tissue was excised 24 h later. Vaginal tissues were sectioned and observed under an EVOS fluorescent microscope with a green filter. L denotes vaginal lumen and S denotes the vagina submucosa. White arrows indicate the vaginal epithelial lining. Red arrows indicate subepithelial penetration of the nanoparticles into the submucosal tissue. Representative images from a single experiment with three animals per condition are shown (Magnification 20×). Fluorescent spots seen within tissues are likely auto-fluorescent neutrophils.