Preparation and characterization of PLGA nano-drug delivery system co-loaded with tranilast/gallium phytate for stent coating

The implantation of bare metal ureteral stents may lead to bacterial colonization and scar hyperplasia. To effectively address these issues, PLGA nanoparticles co-loaded with tranilast and gallium phytate (PG-TRL-PLGA-NPs) were prepared using an emulsifying solvent volatilization technique. The PG-TRL-PLGA-NPs possess a dual function of antibacterial and proliferation inhibition, which could be used for stent functional coating. The PG-TRL-PLGA-NPs displayed a regular spherical morphology with a smooth surface, and average particle size of 163±1.37nm, Zeta potential of -16.09 mV, drug loading capacity of 9.4±0.6%, and encapsulation efficiency of 97.5±0.4% could be achieved. FTIR, XRD, and DSC analysis demonstrated that PG-TRL-PLGA-NPS was successfully nano-encapsulated without chemical reaction among TRL, PG, and PLGA. In vitro release profiles of TRL and gallium ions from PG-TRL-PLGA-NPs exhibited a sustained-release effect, with 89.7±0.9% and 3.2±0.15mg/L released in 14 days, respectively. Furthermore, it was observed the potent antibacterial activity (against S. aureus and E. coli.) of PG-TRL-PLGA-NPs, also significantly inhibited SV-HUC-1 cell proliferation through experiments involving cell migration, cell cycle, and apoptosis studies. These results provide valuable insights into the stent coatings of PG-TRL-PGLA NPs with potential functions of antibacterial and proliferative inhibitory.