Abstract
Nucleoside reverse transcriptase inhibitors (NRTIs) have shown efficacy as pre-exposure prophylaxis (PrEP). The research goal is conjugating NRTIs to biodegradable polymer poly (lactic-co-glycolic acid; PLGA) by an amide bond. NRTIs-PLGA conjugates were chemically activated and conjugated to free amine group of emtricitabine (FTC) and lamivudine (3TC). The conjugates were made into nanoparticles (NPs) and incorporated into a thermosensitive gel for vaginal PrEP. PLGA-FTC and PLGA-3TC NPs were <200nm and zeta potential of-13.7 and -14.1 mV, respectively. The conjugated NPs were not toxic to HeLa cells up to 100 mcg/ml. Thermosensitive gel containing fluorescent NPs fabricated similarly and administered vaginally, were seen in submucosa for up to 5 days. FTC-NPs showed similar EC50 compared to FTC solution. This thermosensitive gel would be a novel vaginal sustained-release PrEP option.