Bioactive coronary stent coating based on layer-by-layer technology for siRNA release.

Area of Science:

• Biomaterials Science
• Nanotechnology
• Cardiovascular Research

Background:

• Percutaneous transluminal coronary angioplasty (PTCA) is used to treat stenotic coronary arteries.
• Drug-eluting stents (DESs) improve outcomes but can be enhanced for better vascular regeneration.
• Small interfering RNA (siRNA) delivery via stents is a promising approach.

Purpose of the Study:

• To develop and evaluate layer-by-layer (LbL) coated coronary stents incorporating siRNA nanoplexes (NPs).
• To assess the stability, cellular uptake, and ex vivo delivery of siRNA NPs from the stent coatings.
• To evaluate the hemocompatibility of the developed bioactive stent coatings.

Main Methods:

• Fabrication of hyaluronic acid/chitosan (HA/Chi) multilayer films with incorporated chitosan-siRNA NPs using LbL technology.
• Characterization of coating thickness and stability using quartz crystal microbalance, fluorescence microscopy, and scanning electron microscopy.
• In vitro assessment of NP uptake by endothelial cells and ex vivo NP transfer into porcine artery walls; hemocompatibility testing.

Main Results:

• Homogeneous HA/Chi and Chi-siRNA NP coatings were successfully fabricated on stents.
• Coatings remained stable after sterilization and stent expansion.
• In vitro studies showed endothelial cell uptake of NPs, and ex vivo studies demonstrated NP transfer into porcine artery walls.
• The developed coatings exhibited good hemocompatibility.

Conclusions:

• Chitosan-siRNA NPs can be effectively incorporated into HA/Chi multilayer films using LbL technology.
• The developed coatings facilitate siRNA NP delivery to endothelial cells in vitro and artery walls ex vivo.
• These bioactive coatings show potential as an innovative tool for coronary stent applications.