Electrospun SLIPS Coatings for Controlled Local Drug Release on Implant Surfaces

Abstract

Postoperative inflammatory reactions and bacterial colonization limit the long-term functionality of implantable medical devices, particularly for implants in permanent contact with biological fluids. Integrating drug delivery directly into implant surfaces offers a way to achieve high local drug concentrations while reducing systemic exposure. In this work, electrospun slippery liquid-infused porous surfaces (SLIPS) are evaluated as implant coatings for controlled local drug delivery, with a focus on how different drug loading strategies and lubricant viscosities influence release behavior. Polycaprolactone (PCL) nanofiber mats were fabricated by electrospinning and subsequently infused with silicone oils of different. Anti-inflammatory and antibiotic model drugs (Dexamethasone and Ciprofloxacin) were incorporated either into the polymer fiber matrix or into the infused lubricant phase. Surface properties were characterized by contact and sliding angle measurements, while drug distribution was analyzed using scanning electron microscopy and Raman spectroscopy. Drug release was quantified under physiological conditions using UV-Vis spectroscopy. Drug incorporation into the polymer fibers resulted in slower and more homogeneous release profiles, whereas lubricant-based loading led to pronounced initial burst release. Increasing lubricant viscosity reduced cumulative release, indicating an additional diffusion barrier effect. These findings show that electrospun SLIPS coatings can be tailored to achieve distinct release profiles and may be suitable for different implantassociated therapeutic scenarios.