Figure 1.

Schematic of semen-triggered release from PSA degradable microgel particles as ‘smart’ microbicide drug delivery vehicles. a) Microgel particles incorporated into a vaginal gel formulation and topically applied to the vaginal epithelium. b) After exposure to semen, the viral carrier, PSA diffuses into the gel and c) begins cleaving degradable peptide-derivatized crosslinkers resulting in triggered release of viral envelope inhibitors into semen. d) HIV is thereby inactivated prior to contact with vaginal tissue and susceptible cells.