Gentamicin-Loaded Chitosan Nanocoating on Polyurethane Prostatic Stents to Combat Biofilm Formation and Urogenital Device-Associated Infections.

Prostatic obstruction is a blockage of the urethra caused by benign prostatic hyperplasia, a common condition in aging men that often results in significant urinary complications. Polyurethane prostatic stents are widely used to alleviate this obstruction. However, their susceptibility to biofilm formation and subsequent bacterial infections by pathogens such as Escherichia coli and Proteus mirabilis remains a major clinical challenge. This study investigates the polyurethane prostatic stents (PS) that are surface-immobilized with gentamicin-loaded chitosan nanoparticles (GMCSNPs) to combat these issues. GMCSNPs were synthesized via the ionic gelation method, achieving high drug encapsulation efficiency (92.32%) and exhibiting a spherical morphology, as confirmed by field emission scanning electron microscopy (FESEM); particle size was determined using a Zetasizer. The nanoparticles had a size range of 200-350 nm. The surface of polyurethane prostatic stents was activated and covalently immobilized with GMCSNPs, as confirmed through attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) and FESEM analyses. The antimicrobial efficacy of GMCSNPs and GMCSNPs-immobilized polyurethane prostatic stents (GMCSNPs-PS) was evaluated against E. coli and P. mirabilis. Bacterial viability assays, flow cytometry, and biofilm inhibition studies revealed significant antibacterial activity and a marked reduction in biofilm formation. The sustained release of gentamicin, combined with the intrinsic antimicrobial properties of chitosan, demonstrated a synergistic effect, successfully inhibiting bacterial growth and biofilm development.