One-step lipid-polymeric hybrid nanoparticles as intracanal drug delivery system: Synthesis, characterization, antimicrobial activity, and dentinal penetration.

INTRODUCTION

This study developed two lipid-polymeric hybrid nanoparticle thermosensitive gels, hypothesizing enhanced physicochemical properties, antimicrobial efficacy, and dentinal penetration compared to free drugs.

METHODS

Ciprofloxacin-loaded lecithin-PLGA nanoparticles (CIP-LPNPs) and chitosan-lecithin nanoparticles (CS-LNPs) were synthesized via nanoprecipitation and characterized by DLS, SEM, FTIR and HPLC. Antimicrobial activity against Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa was assessed by disk diffusion, MIC and biofilm assays; dentinal penetration of FITC-labeled CS-LNPs was evaluated by confocal microscopy.

RESULTS

CIP-LPNPs and CS-LNPs measured 140.6 and 130.9 nm with zeta potentials of -29.4 and +28.9 mV, respectively. CIP-LPNPs showed 55.7% encapsulation and biphasic release. Both nanoparticles enhanced biofilm eradication against all strains; CS-LNPs exhibited two-fold lower MICs and significantly deeper tubular penetration than free chitosan (p < 0.0001).

CONCLUSIONS

Both CIP-LPNPs and CS-LNPs improved physicochemical and antibiofilm properties over their free drugs; however, as no biocompatibility assessment was performed, these formulations cannot be considered safe without such validation.